bluuebunny/crossref_metadata_2025_split huggingface dataset:
A high‐performance liquid chromatographic analysis and preliminary pharmacokinetic characterization of 3′‐hydroxypterostilbene in rats
Authors: Takemoto Jody K. , Davies Neal M. 
Published: April 2009

AbstractA high‐performance liquid chromatographic method was developed for the analysis of 3'‐hydroxypterostilbene. This method involves the use of a Luna® C18 column with ultraviolet detection at 325 nm. The mobile phase consisted of acetonitrile, water and formic acid (50:50:0.01, v/v/v) with a flow rate of 0.8 mL/min. The calibration curves were linear over the range 0.5–100.0 µg/mL. The mean extraction efficiency was between 97.40 and 111.16%. The precision of the assay was 0.196–14.39% (RSD%), and within 15% at the limit of quantitation (0.5 µg/mL). The bias of the assay was <16% and within 15% at the limit of quantitation. This assay was successfully applied to pre‐clinical pharmacokinetic samples from rat urine and serum. Copyright © 2009 John Wiley & Sons, Ltd.
Using process simulators in the study, design, and control of distillation columns for undergraduate chemical engineering courses
Authors: Castrellón T. , Botía D. C. , Gómez R. , Orozco G. , Gil I. D. 
Published: April 2009

AbstractNowadays high schools should teach students how to use the software that they will use at work. This article shows the importance to promote a closer relationship between the engineering computer programs offered by companies like Aspen Technology Inc., and the chemical engineering students. The methodology consists of creating a tutorial which illustrates, in an interesting way, subjects through engineering software packages. The main theme treated in this tutorial is distillation column simulation and design; it also includes a brief look into distillation column control by means of dynamic simulations. This article presents an interactive guide with three case studies, where the subjects of design and control for a binary simple system and the development of a simulation for a complex ternary system are studied. These guides were implemented in Separation Processes and Process Design courses and the guide evaluation results show an acceptance by the students. © 2009 Wiley Periodicals, Inc. Comput Appl Eng Educ 19: 621–630, 2011
GilR, an Unusual Lactone‐Forming Enzyme Involved in Gilvocarcin Biosynthesis
Authors: Kharel Madan Kumar , Pahari Pallab , Lian Hui , Rohr Jürgen 
Published: April 2009

AbstractLast at last: The terminal step of the gilvocarcin V (GV) biosynthetic pathway is an unusual lactone formation. Here we show that the enzyme, GilR, dehydrogenates the hemiacetal moiety of pregilvocarcin V to the lactone found in GV by using covalently bound FAD.magnified image
Michael Additions versus Cycloaddition Condensations with Ethyl Nitroacetate and Electron‐Deficient Olefins
Authors: Trogu Elena , De Sarlo Francesco , Machetti Fabrizio 
Published: April 2009

AbstractEthyl nitroacetate (1) reacts with electron‐poor olefins in the presence of a base to give either the Michael adducts 3 or the isoxazoline cycloadducts 4, resulting from water elimination. The proportions of the two products depend on the reaction conditions and change in the course of the process. Kinetic profiles for the two reactions show that the cycloaddition‐condensations require long induction times that dramatically decrease upon addition of a copper salt to the catalytic system: the drops in the induction time cause increases in the proportion of cycloadducts 4, which are often the sole reaction products. This is the first report on the selective formation of products 3 and 4 from primary nitro compounds through modulation of the catalytic system.
Coherently Aligned Porphyrin‐Appended Polynorbornenes
Authors: Wang Hsian‐Wen , Liu Zhi‐Chang , Chen Chih‐Hsien , Lim Tsong‐Shin , Fann Wunshain , Chao Chih‐Gang , Yu Jian‐Yuan , Lee Shern‐Long , Chen Chun‐hsien , Huang Shou‐Ling , Luh Tien‐Yau 
Published: April 2009

AbstractYou can append on me! Porphyrin‐appended polynorbornenes derived from 5,6‐endo‐fused N‐arylpyrrolidenonorbornenes have been shown to have coherently aligned pendant groups that exhibit exciton coupling and fluorescence quenching in the absorption and emission profiles (see figure).magnified imageSix different kinds of coherently aligned porphyrin‐appended polynorbornenes derived from 5,6‐endo‐fused N‐arylpyrrolidenonorbornenes have been synthesized. π–π interactions between the pendant groups are essential for dictating the photophysical properties of the polymers and the mechanism for the stereoselective formation of polymers. Splitting of the Soret band of polymers 2 a–c, which have alkyl‐substituted porphyrin pendant groups, suggests strong exciton coupling between chromophores. No splitting of the Soret band is observed for polymers 2 d–f, which have tetraaryl substituents on the porphyrin moiety. Significant fluorescence quenching is found in polymers 2 a–e, whereas only slightly reduced quantum yield is observed for 2 f. Time‐resolved fluorescence measurements also indicate a similar trend. The AFM image of 2 d on graphite shows aggregation to form a two‐dimensional, ordered pattern.
Self‐Assembly of Mn‐Doped ZnS Quantum Dots/Octa(3‐aminopropyl)octasilsequioxane Octahydrochloride Nanohybrids for Optosensing DNA
Authors: He Yu , Wang He‐Fang , Yan Xiu‐Ping 
Published: April 2009

AbstractSimple plan! Nanohybrids have been built from capped Mn‐doped ZnS quantum dots and octa(3‐aminopropyl)octasilsequioxane octahydrochloride (OA‐POSS) by means of electrostatic self‐assembly for the development of a novel room‐temperature phosphorescence sensor for DNA sensing in biological fluids (see graphic).magnified image
Solid‐State Structure of Free Base Guanidine Achieved at Last
Authors: Yamada Takahiro , Liu Xiaohui , Englert Ulli , Yamane Hisanori , Dronskowski Richard 
Published: April 2009

Abstract“Crystal structure of the free base guanidine determined 148 years after the first synthesis”: A prototype structure unveiled—despite its provocative simplicity, the crystal structure of guanidine has not been previously described. 148 years after the first synthesis of guanidine, we now find two Y‐shaped symmetry‐independent molecules in the unit cell that are interconnected by a hydrogen‐bonding network, which results in a fascinating layered structure (see picture).magnified image
Cover Picture: Minerals as Molecules—Use of Aqueous Oxide and Hydroxide Clusters to Understand Geochemical Reactions (Chem. Eur. J. 18/2009)
Authors: Casey William H. , Rustad James R. , Spiccia Leone 
Published: April 2009

AbstractA model nanoparticle respresenting goethite (α‐FeOOH), an important soil mineral, is depicted in the center of the cover picture. The solvent‐accessible surface is represented by the translucent material, and the surface oxygen atoms are represented with spheres. The colors of the spheres give their average protonation states over the course of a molecular dynamics simulation, with red denoting FeOH2 groups and blue denoting FeOH groups. Iron or aluminum Baker–Figgis–Keggin isomers are shown in the corners. For more details on the chemistry of minerals see the Concept article by W. H. Casey, J. R. Rustad and L. Spiccia on page 4496 ff.magnified image
Target‐Based Drug Discovery: the Emerging Success of Frontal Affinity Chromatography Coupled to Mass Spectrometry
Authors: Calleri Enrica , Temporini Caterina , Caccialanza Gabriele , Massolini Gabriella 
Published: April 2009

AbstractFrontal affinity chromatography coupled to mass spectrometry (FAC–MS) has been reported as a potential method for screening compound mixtures against immobilized target proteins. The potentiality of this analytical approach is described and illustrated with a number of examples based on targets of pharmaceutical interest.magnified image
Derivation of a Retinoid X Receptor Scaffold from Peroxisome Proliferator‐Activated Receptor γ Ligand 1‐Di(1H‐indol‐3‐yl)methyl‐4‐trifluoromethylbenzene
Authors: Dawson Marcia I. , Ye Mao , Cao Xihua , Farhana Lulu , Hu Qiong‐Ying , Zhao Yong , Xu Li Ping , Kiselyuk Alice , Correa Ricardo G. , Yang Li , Hou Tingjun , Reed John C. , Itkin‐Ansari Pamela , Levine Fred , Sanner Michel F. , Fontana Joseph A. , Zhang Xiao‐Kun 
Published: April 2009

AbstractPPARγ agonist DIM‐Ph‐4‐CF3, a template for RXRα agonist (E)‐3‐[5‐di(1‐methyl‐1H‐indol‐3‐yl)methyl‐2‐thienyl] acrylic acid: DIM‐Ph‐CF3 is reported to inhibit cancer growth independent of PPARγ and to interact with NR4A1. As both receptors dimerize with RXR, and natural PPARγ ligands activate RXR, DIM‐Ph‐4‐CF3 was investigated as an RXR ligand. It displaces 9‐cis‐retinoic acid from RXRα but does not activate RXRα. Structure‐based direct design led to an RXRα agonist.magnified image1‐Di(1H‐indol‐3‐yl)methyl‐4‐trifluoromethylbenzene (DIM‐Ph‐4‐CF3) is reported to inhibit cancer cell growth and to act as a transcriptional agonist of peroxisome proliferator‐activated receptor γ (PPARγ) and nuclear receptor 4A subfamily member 1 (NR4A1). In addition, DIM‐Ph‐4‐CF3 exerts anticancer effects independent of these receptors because PPARγ antagonists do not block its inhibition of cell growth, and the small pocket in the NR4A1 crystal structure suggests no ligand can bind. Because PPARγ and NR4A1 heterodimerize with retinoid X receptor (RXR), and several PPARγ ligands transcriptionally activate RXR, DIM‐Ph‐4‐CF3 was investigated as an RXR ligand. DIM‐Ph‐4‐CF3 displaces 9‐cis‐retinoic acid from RXRα but does not transactivate RXRα. Structure‐based design using DIM‐Ph‐4‐CF3 as a template led to the RXRα transcriptional agonist (E)‐3‐[5‐di(1‐methyl‐1H‐indol‐3‐yl)methyl‐2‐thienyl]acrylic acid. Its docked pose in the RXRα ligand binding domain suggests that binding is stabilized by interactions of its carboxylate group with arginine 316, its indoles with cysteines 269 and 432, and its 1‐methyl groups with hydrophobic residues lining the binding pocket. As is expected of a selective activator of RXRα, but not of RARs and PPARγ, this RXRα agonist, unlike DIM‐Ph‐4‐CF3, does not appreciably decrease cancer cell growth or induce apoptosis at pharmacologically relevant concentrations.
Unlocking the Chemotherapeutic Potential of β‐Aminovinyl Ketones and Related Compounds
Authors: Gaber Hatem M. , Bagley Mark C. 
Published: April 2009

AbstractThe role of β‐aminovinyl ketonesas synthetic intermediates has been well categorised, but recent developments have shown an interesting array of applications and new chemotherapeutic potential, both in the preparation of biologically active heterocycles and as pharmacophores in their own right.magnified imageMedicinal chemists are accustomed to using the products of Knoevenagel‐type condensations as auxiliaries for the synthesis of N‐containing heteroaromatic compounds. One such example of these chemical building blocks are β‐aminovinyl ketones—valuable synthetic intermediates that have been used in the preparation of pyridines, pyrimidines, pyrazoles, and many other heterocyclic motifs. This review highlights their recent use in the synthesis of biologically active targets as part of drug discovery programmes and in natural product synthesis. However, it is becoming increasingly evident that the enaminone motif may serve as a therapeutic pharmacophore in its own right. This review highlights the range of biological responses that β‐aminovinyl ketones elicit, including as antitumour, antibacterial, and anticonvulsant agents. Thus, with a broad spectrum of biological properties and as versatile chemical intermediates, it is clear that β‐aminovinyl ketones offer great potential in the search for new chemotherapeutic agents.
Applications of parallel processing technologies in heuristic search planning: methodologies and experiments
Authors: Phan Tu Huy , Pontelli Enrico , Son Tran Cao , To Son Thanh 
Published: April 2009

AbstractThe goal of this paper is to investigate the application of parallel programming techniques to boost the performance of heuristic search‐based planning systems in various aspects. It shows that an appropriate parallelization of a sequential planning system often brings gain in performance and/or scalability. We start by describing general schemes for parallelizing the construction of a plan. We then discuss the applications of these techniques to two domain‐independent heuristic search‐based planners—a competitive conformant planner (CPA) and a state‐of‐the‐art classical planner (FF). We present experimental results—on both shared memory and distributed memory platforms—which show that the performance improvements and scalability are obtained in both cases. Finally, we discuss the issues that should be taken into consideration when designing a parallel planning system and relate our work to the existing literature. Copyright © 2009 John Wiley & Sons, Ltd.
Dynamic file system semantics to enable metadata optimizations in PVFS
Authors: Kuhn Michael , Kunkel Julian Martin , Ludwig Thomas 
Published: April 2009

AbstractModern file systems maintain extensive metadata about stored files. While metadata typically is useful, there are situations when the additional overhead of such a design becomes a problem in terms of performance. This is especially true for parallel and cluster file systems, where every metadata operation is even more expensive due to their architecture. In this paper several changes made to the parallel cluster file system Parallel Virtual File System (PVFS) are presented. The changes target at the optimization of workloads with large numbers of small files. To improve the metadata performance, PVFS was modified such that unnecessary metadata is not managed anymore. Several tests with a large quantity of files were performed to measure the benefits of these changes. The tests have shown that common file system operations can be sped up by a factor of two even with relatively few changes. Copyright © 2009 John Wiley & Sons, Ltd.
A numerical model for the oscillation frequency, the amplitude and the phase‐noise of MOS‐current‐mode‐logic ring oscillators
Authors: Nocente Michele , Fontanelli Donald , Palestri Pierpaolo , Nonis Roberto , Esseni David , Selmi Luca 
Published: April 2009

AbstractThis paper presents a new model for the frequency of oscillation, the oscillation amplitude and the phase‐noise of ring oscillators consisting of MOS‐current‐mode‐logic delay cells. The numerical model has been validated through circuit simulations of oscillators designed with a typical 130 nm CMOS technology. A design flow based on the proposed model and on circuit simulations is presented and applied to cells with active loads. The choice of the cell parameters that minimize phase‐noise and power consumption is addressed. Copyright © 2009 John Wiley & Sons, Ltd.
The voltage mirror–current mirror pair as a universal element
Authors: Soliman Ahmed M. , Saad Ramy A. 
Published: April 2009

AbstractThe voltage mirror–current mirror (VM–CM) pair is shown to be a universal active element. It provides two alternative realizations for the nullor. The VM–CM pair is also capable of realizing the op amp and all the four types of the current conveyors namely CCII−, CCII+, ICCII− and ICCII+ as special cases. Copyright © 2009 John Wiley & Sons, Ltd.
Induction of DNA damage response by the supravital probes of nucleic acids
Authors: Zhao Hong , Traganos Frank , Dobrucki Jurek , Wlodkowic Donald , Darzynkiewicz Zbigniew 
Published: April 2009

AbstractThe aim of this study was to assess the potential DNA damage response (DDR) to four supravitally used biomarkers Hoechst 33342 (Ho 42), DRAQ5, DyeCycle Violet (DCV), and SYTO 17. A549 cells were exposed to these biomarkers at concentrations generally applied to live cells and their effect on histone H2AX (Ser 139), p53 (Ser15), ATM (Ser1981), and Chk2 (Thr68) phosphorylation was assessed using phospho‐specific Abs. Short‐term treatment with Ho 42 led to modest degree of ATM activation with no evidence of H2AX, Chk2, or p53 phosphorylation. However, pronounced ATM, Chk2, and p53 phosphorylation and perturbed G2 progression were seen after 18 h. While short‐term treatment with DRAQ5 induced ATM activation with no effect on H2AX, Chk2, and p53, dramatic changes marked by a high degree of H2AX, ATM, Chk2, and p53 phosphorylation, all occurring predominantly in S phase cells, and a block in cell cycle progression, were seen after 18 h exposure. These changes suggest that the DRAQ5‐induced DNA lesions may become converted into double‐strand DNA breaks during replication. Exposure to DCV also led to an increase in the level of activated ATM and Chk2 as well as of phosphorylated p53 and accumulation of cells in G2M and S phase. Exposure to SYTO 17 had no significant effect on any of the measured parameters. The data indicate that supravital use of Ho 42, DRAQ5, and DCV induces various degrees of DDR, including activation of ATM, Chk2 and p53, which may have significant consequences on regulatory cell cycle pathways and apoptosis. © 2009 International Society for Advancement of Cytometry.
Nachweis der Feuerwiderstandsdauer von Ziegeldecken durch Kombination von Versuch und Simulation
Authors: Jäger Wolfram , Ortlepp Sebastian 
Published: April 2009

AbstractDer Nachweis der Feuerwiderstandsdauer von Ziegeldecken erfolgte bisher i. d. R. über Brandversuche, die sehr aufwendig und teuer sind. Der Beitrag zeigt, wie durch Kombination von Versuch, Simulation und ingenieurmäßiger Betrachtung eine bedeutende Aufwandsreduzierung erreicht werden kann.Im Rahmen der Typenstatik von zwei Ziegeldecken Typ 22 (17+5) und Typ 25 (20+5) konnte ohne Estrich und Putz die Feuerwiderstandsdauer F60‐A erreicht werden. Mit einem zusätzlichen unterseitigen Putz (1cm Gipsputz) und mit einem schwimmenden Estrich (≥ 2,5 cm) wurde die Klasse F90‐A erreicht. Um die Feuerwiderstandsklasse F90‐A für Typ 22 und Typ 25 auch ohne Putz und Estrich zu erreichen, wurde für den Deckentyp mit Aufbeton Typ22 (17+5) eine Brandprüfung durchgeführt. Ausgehend von den Ergebnissen dieses Versuches fand eine weitergehende Auswertung und Verallgemeinerung auf andere Deckentypen statt, die nachfolgend vorgestellt wird.
Deutschland braucht neue Wohnungen – Kampagne für den Wohnungsbau
Authors: Rast Ronald 
Published: April 2009

AbstractDie Anfang 2009 gestartete Kampagne “Impulse für den Wohnungsbau” setzt sich für eine Verbesserung der bestehenden politischen Rahmenbedingungen im Wohnungsbau ein. Hintergrund ist der bestehende Mangel an bezahlbaren und geeigneten Wohnungen. Obwohl jährlich 400000 Wohnungen benötigt werden, wurden in 2008 weniger als 200000 fertiggestellt. Die Deutsche Gesellschaft für Mauerwerksbau und der Bundesverband Deutscher Baustoff‐Fachhandel engagieren sich gemeinsam mit weiteren Verbänden und Unternehmen aus dem Wohnungsbau und der Immobilienwirtschaft für das Grundbedürfnis Wohnen. Gemeinsames Ziel ist, die Handlungsfelder der Zukunft auf die politische Agenda zu setzen: Die Menschen in Deutschland brauchen bezahlbare, barrierefreie und energieeffiziente Wohnungen.
Accuracy of a low priced liquid‐based method for cervical cytology in 632 women referred for colposcopy after a positive Pap smear
Authors: van Hemel B. M. , Buikema H. J. , Groen H. , Suurmeijer A. J. H. 
Published: April 2009

AbstractThe aim of this quality controlling study was to determine the accuracy of liquid‐based cytology (LBC) with the Turbitec® cytocentrifuge technique. Cervical smears of 632 women, who were referred to our CIN outpatient department, after at least two smears with ASCUS or higher were evaluated and compared with the histological outcome. In 592 cases the smears revealed abnormalities of squamous epithelium, and in 40 cases the abnormalities of glandular epithelium. In the group of squamous epithelium abnormalities, the sensitivity for LSIL was 39.7% and the specificity was 89.2%; for the LSIL+ group, these values were 89.4% and 91.4%, respectively. For HSIL the sensitivity was 68.3% and the specificity 92.8%, for the HSIL+ group 82.3% and 92.3%, respectively. The ASCUS rate was low (2.4%). The Turbitec cytocentrifuge method was proved to be a very good LBC method for cervical smears. Because of a comparable accuracy together with a lower price, this LBC method outweighs commercial alternatives. Diagn. Cytopathol. 2009. © 2009 Wiley‐Liss, Inc.
Hodgkin's lymphoma: Diagnostic difficulties in fine‐needle aspiration cytology
Authors: Das Dilip K. , Francis Issam M. , Sharma Prem N. , Sathar Sitara A. , John Bency , George Sara S. , Mallik Mrinmay K. , Sheikh Zaffar A. , Haji Bahiyah E. , Pathan Shahed K. , Madda John P. , Mirza Kahvic , Ahmed Mahamoud S. , Junaid Thamradeen A. 
Published: April 2009

AbstractIt is commonly believed that cytodiagnosis of Hodgkin's lymphoma (HL) is much easier than that of non‐Hodgkin lymphoma (NHL). However, recognition of certain NHL subtypes with Reed‐Sternberg (R‐S)‐like cells and results of immunohistochemical studies point to the contrary. To study the limitations of cytology in diagnosis of HL, fine‐needle aspiration (FNA) smears of 130 lymphoma or suspected lymphoma cases were reviewed. Initial and reviewed cytodiagnoses were compared with histopathology in 89 cases. Immunocytochemical and immunohistochemical studies were performed in 56 and 59 cases, respectively. Among histologically diagnosed HL cases, definitive cytodiagnosis of HL (initial as well as reviewed) was significantly less frequent than cytodiagnosis of NHL among histologically diagnosed NHL cases (P = 0.0328 and = 0.0001, respectively). On the other hand, cytologically diagnosed HL/NHL cases were significantly more frequent in the former group (P = 0.0001 and = 0.0018, respectively). ALCL and TCRBCL were the two NHL subtypes which created confusion with HL in FNA smears. Twenty‐one cytohistological concordant HL cases and equal number of discordant cases were compared. When compared with discordant group, the patients in concordant group were significantly younger (P = 0.045). Hodgkin/Hodgkin‐like cells and typical R‐S cells were significantly more frequent in FNA smears of the concordant group (P = 0.0478 and = 0.0431, respectively). Immunocytochemical and immunohistochemical studies showed good correlation with histological diagnosis of HL. It is suggested that proper interpretation of cytologic features, together with use of immunocytochemical parameters can help in reducing the margin of error in cytodiagnois of HL. Diagn. Cytopathol. 2009. © 2009 Wiley‐Liss, Inc.
Epithelioid cell cluster in cerebrospinal fluid: An unusual finding in tubercular meningitis
Authors: Arif S. H. , Rahman Khaliqur , Khalid Mohammad , Hassan Mohd. Jaseem , Qaseem S. M. Danish , Huda Md. Fakhrul 
Published: April 2009

AbstractTubercular meningitis is one of the serious manifestations of tuberculosis. It remains a significant contributor to the morbidity and mortality in children. Meningeal involvement in tuberculosis is detected by physical, chemical and cytological examination of cerebrospinal fluid (CSF). The cytological picture of CSF in tubercular meningitis is quite similar to that of viral meningitis showing a mixed population of lymphoid series cells. The presence of epithelioid cell cluster is very rare finding. We present here such a case of 2½ yr old boy who presented with fever off and on for 2 months and altered sensorium along with vomiting for 2–3 days. Diagn. Cytopathol. 2009. © 2009 Wiley‐Liss, Inc.