bluuebunny/crossref_metadata_2025_split huggingface dataset:
Surface Dynamics of A Vanadyl Pyrophosphate Catalyst for n‐Butane Oxidation to Maleic Anhydride: An In Situ Raman and Reactivity Study of the Effect of the P/V Atomic Ratio
Authors: Cavani Fabrizio , Luciani Silvia , Esposti Elisa Degli , Cortelli Carlotta , Leanza Roberto 
Published: December 2009

AbstractThis work focused on investigating the effect of the P/V atomic ratio in vanadyl pyrophosphate, catalyst for n‐butane oxidation to maleic anhydride, on the nature of the catalytically active phase. Structural transformations occurring on the catalyst surface were investigated by means of in situ Raman spectroscopy in a non‐reactive atmosphere, as well as by means of steady‐state and non‐steady‐state reactivity tests, in response to changes in the reaction temperature. It was found that the nature of the catalyst surface is affected by the P/V atomic ratio even in the case of small changes in this parameter. With the catalyst having P/V equal to the stoichiometric value, a surface layer made of αI‐VOPO4 developed in the temperature interval 340–400 °C in the presence of air; this catalyst gave a very low selectivity to maleic anhydride in the intermediate T range (340–400 °C). However, at 400–440 °C δ‐VOPO4 overlayers formed; at these conditions, the catalyst was moderately active but selective to maleic anhydride. With the catalyst containing a slight excess of P, the ratio offering the optimal catalytic performance, δ‐VOPO4 was the prevailing species over the entire temperature range investigated (340–440 °C). Analogies and differences between the two samples were also confirmed by reactivity tests carried out after in situ removal and reintegration of P. These facts explain why the industrial catalyst for n‐butane oxidation holds a slight excess of P; they also explain discrepancies registered in the literature about the nature of the active layer in vanadyl pyrophosphate.
N‐Heterocyclic Carbene (NHC)‐Stabilized Silanechalcogenones: NHC→Si(R2)E (E=O, S, Se, Te)
Authors: Yao Shenglai , Xiong Yun , Driess Matthias 
Published: December 2009

AbstractA series of N‐heterocyclic carbene‐stabilized silanechalcogenones 2 a,b (SiO), 3 a,b (SiS), 4 a,b (SiSe), and 5 a,b (SiTe) are described. The silanone complexes 2 a,b were prepared by facile oxygenation of the carbene–silylene adducts 1 a,b with N2O, whereas their heavier congeners were synthesized by gentle chalcogenation of 1 a,b with equimolar amounts of elemental sulfur, selenium, and tellurium, respectively. These novel compounds have been isolated in a crystalline form in high yields and have been fully characterized by a variety of techniques including IR spectroscopy, ESIMS, and multinuclear NMR spectroscopy. The structures of 2 b, 3 a, 4 a, 4 b, and 5 b have been confirmed by single‐crystal X‐ray crystallography. Due to the NHC→Si donor–acceptor electronic interaction, the SiE (E=O, S, Se, Te) moieties within these compounds are well stabilized and thus the compounds possess several ylide‐like resonance structures. Nevertheless, these species also exhibit considerable SiE double‐bond character, presumably through a nonclassical SiE π‐bonding interaction between the chalcogen lone‐pair electrons and two antibonding SiN σ* orbitals, as evidenced by their high stretching vibration modes and the shortening of the Si–E distances (between 5.4 and 6.3 %) compared with the corresponding SiE single‐bond lengths.
Spatially Controllable DNA Condensation by a Water‐Soluble Supramolecular Hybrid of Single‐Walled Carbon Nanotubes and β‐Cyclodextrin‐Tethered Ruthenium Complexes
Authors: Yu Miao , Zu Sheng‐Zhen , Chen Yong , Liu Yu‐Ping , Han Bao‐Hang , Liu Yu 
Published: December 2009

AbstractA supramolecular hybrid is prepared by the supramolecular surface modification of single‐walled carbon nanotube (SWCNT) with cationic β‐cyclodextrin‐tethered ruthenium complexes through a spacer molecule that contains both an adamantane and a pyrene moiety. By employing the supramolecular hybrid, spatially controllable DNA condensation along the SWCNT skeleton is achieved by anchoring cationic ruthenium complexes on the surface. Furthermore, because of the unique physiological properties of SWCNTs, the cationic supramolecular hybrid can be used as a nonviral gene delivery system with the ruthenium complexes as a fluorescent probe to monitor uptake of DNA by cells.
Asymmetric Synthesis of α‐Tocopherol
Authors: Hengartner Urs , Chougnet Antoinette , Liu Kegang , Woggon Wolf‐D. 
Published: December 2009

Abstractα‐Tocopherol was synthesized from a chiral intermediate α‐hydroxy ester by means of two ring‐closing methods to yield the chromanol in 94 % diastereomeric excess.
Externes Numbering‐up für Flüssig/Flüssig‐Systeme in Kapillarreaktoren
Authors: Mendorf M. , Nachtrodt H. , Agar D. 
Published: December 2009

AbstractIn der vorliegenden Studie wurden vier verschiedene Verteilerkonzepte zur Fluidverteilung auf acht Kapillaren hinsichtlich ihrer Güte der Gleichverteilung einer parallelisierten zweiphasigen Pfropfenströmung untersucht. Zunächst wurden alle Verteilergeometrien mit angepassten Fluidwiderständen versehen und gezeigt, dass Fertigungstoleranzen aller Bauteile spezifisch ausgeglichen werden können. Es resultierten Standardabweichungen der Volumenstromaufteilungen mit einphasigen Stoffsystemen von weniger als 1 % für alle Geometrien. Bei der zweiphasigen Flüssig/Flüssig‐Pfropfenströmung gestaltet sich die Vergleichmäßigung deutlich komplexer. Es konnte maximal eine Standardabweichung von 4 % erreicht werden. Die Abweichungen resultieren aus der stochastisch geprägten Pfropfenerzeugung sowie Koaleszenzerscheinungen und sich zeitlich verändernden Benetzungseigenschaften der verwendeten Werkstoffe.
Artemisinin antimalarials: preserving the “magic bullet”
Authors: Maude Richard J. , Woodrow Charles J. , White Lisa J. 
Published: December 2009

AbstractThe artemisinins are the most effective antimalarial drugs known. They possess a remarkably wide therapeutic index. These agents have been used in traditional Chinese herbal medicine for more than 2,000 years but were not subjected to scientific scrutiny until the 1970s. The first formal clinical trials of the artemisinins, and the development of methods for their industrial scale production, followed rapidly. A decade later, Chinese scientists shared their findings with the rest of the world; since then, a significant body of international trial evidence has confirmed these drugs to be far superior to any available alternatives. In particular, they have the ability to rapidly kill a broad range of asexual parasite stages at safe concentrations that are consistently achievable via standard dosing regimens. As their half‐life is very short, there was also thought to be a low risk of resistance. These discoveries coincided with the appearance and spread of resistance to all the other major classes of antimalarials. As a result, the artemisinins now form an essential element of recommended first‐line antimalarial treatment regimens worldwide. To minimize the risk of artemisinin resistance, they are recommended to be used to treat uncomplicated malaria in combination with other antimalarials as artemisinin combination therapies (ACTs). Their rollout has resulted in documented reductions in malaria prevalence in a number of African and Asian countries. Unfortunately, there are already worrisome early signs of artemisinin resistance appearing in western Cambodia. If this resistance were to spread, it would be disastrous for malaria control efforts worldwide. The enormous challenge for the international community is how to avert this catastrophe and preserve the effectiveness of this antimalarial “magic bullet”. Drug Dev Res 71: 12–19, 2010. © 2009 Wiley‐Liss, Inc.
Targeting the lipid metabolic pathways for the treatment of malaria
Authors: Ben Mamoun Choukri , Prigge Sean T. , Vial Henri 
Published: December 2009

AbstractThe control and eventual eradication of human malaria is considered one of the most important global public health goals of the 21st Century. Malaria, caused by intraerythrocytic protozoan parasites of the genus Plasmodium, is by far the most lethal and among the most prevalent of the infectious diseases. Four species of Plasmodium (P. falciparum, P. malariae, P. ovale, and P. vivax) are known to be infectious to humans, and more recent cases of infection due to P. knowlesi also have been reported. These species cause approximately 300 million annual cases of clinical malaria resulting in around one million deaths mostly caused by P. falciparum. The rapid emergence of drug‐resistant Plasmodium strains has severely reduced the potency of medicines commonly used to treat and block the transmission of malaria and threatens the effectiveness of combination therapy in the field. New drugs that target important parasite functions, which are not the target of current antimalarial drugs, and have the potential to act against multi‐drug‐resistant Plasmodium strains are urgently needed. Recent studies in P. falciparum have unraveled new metabolic pathways for the synthesis of the parasite phospholipids and fatty acids. The present review summarizes our current understanding of these pathways in Plasmodium development and pathogenesis, and provides an update on the efforts underway to characterize their importance using genetic means and to develop antimalarial therapies targeting lipid metabolic pathways. Drug Dev Res 71:44–55, 2010. © 2009 Wiley‐Liss, Inc.
Antiparasitic and immunomodulatory activities of 1,1‐bis(4‐hydroxyphenyl)‐2‐phenyl‐but‐1‐ene and its protected and free 2‐ferrocenyl derivatives
Authors: Soares Milena B.P. , Costa José Fernando Oliveira , Santos de Sá Matheus , Ribeiro‐dos‐Santos Ricardo , Pigeon Pascal , Jaouen Gérard , Santana Antônio Euzébio G. , Goulart Marilia O.F. , Hillard Elizabeth 
Published: December 2009

AbstractThe ferrocenyl diphenol 1 [1,1‐bis(4‐hydroxyphenyl)‐2‐ferrocenyl‐but‐1‐ene] displays strong cytotoxic effects against a variety of cancer cells. In the present study we have evaluated the immunomodulatory and antiparasitic activities of compound 1 and its protected dipalmitate analogue 2. We have furthermore compared the antiparasitic results of 1 and 2 with the organic analogue, 3 [1,1‐bis(4‐hydroxyphenyl)‐2‐phenyl‐but‐1‐ene], where the ferrocenyl group has been replaced by a phenyl ring. When assayed against normal (noncancerous) splenocytes, all compounds were considered nontoxic. Compound 1 inhibited NO production by macrophages, inhibited concanavalin A‐induced lymphoproliferation, and was active against Leishmania amazonensis and Trypanosoma cruzi. Compound 2 had lower activity in all assays performed. Surprisingly, compounds 1 and 2 exhibited similar and significant activity against Plasmodium falciparum, with IC50 values of 3.50 and 1.33 µM, respectively. Compound 3 showed an inverse activity profile, being active against T. cruzi but far less active against P. falciparum. Drug Dev Res 71: 69–75, 2010. © 2009 Wiley‐Liss, Inc.
Antimalarial preclinical drug development: a single oral dose of a 5‐carbon‐linked trioxane dimer plus mefloquine cures malaria‐infected mice
Authors: Moon Deuk Kyu , Singhal Vandana , Kumar Nirbhay , Shapiro Theresa A. , Posner Gary H. 
Published: December 2009

AbstractThree new 5‐carbon‐linked trioxane dimer carboxylate esters have been prepared from the natural trioxane, artemisinin, in only three steps and 40–50% overall yields. Each one of these new chemical entities is at least as efficacious as the clinically used trioxane antimalarial drug artemether when combined with mefloquine hydrochloride in a low single oral dose cure. Drug Dev Res 71: 76–81, 2010. © 2009 Wiley‐Liss, Inc.
Antimalarial activity of compounds and mixed fractions of Cecropia pachystachya
Authors: Uchôa Valdiléia Teixeira , de Paula Renata Cristina , Krettli Luísa G. , Santana Antônio Euzébio Goulart , Krettli Antoniana Ursine 
Published: December 2009

AbstractExtracts from Cecropia pachystachya (Cecropiaceae), a medicinal plant used in Brazil, were tested for their antimalarial activity against Plasmodium falciparum and/or Plasmodium berghei in mice. The ethanol extracts of wood, root, and leaves reduce parasitemia of malaria‐infected mice from 35–66% in relation to nontreated control mice. The plant roots extracts, with stronger activity, were further analyzed and provided subfractions also active in vivo from which two compounds were isolated and chemically characterized as β‐sitosterol and tormentic acid. Although both compounds were active in mice malaria, only the tormentic acid inhibited P. falciparum chloroquine‐resistant parasites (W2) growth in cultures, reducing parasitemia dose‐responsively (IC50=11–15 µg/ml). The antimalarial activity of the plant extracts kept refrigerated 7 years after the initial isolation, when tested in parallel with new extracts freshly isolated from plants collected at the same geographical site, was similar, confirming the superiority of the plant roots and the stability of the active extracts. In these experiments, inhibition of parasite growth was measured by hypoxanthine incorporation and by immunoenzymatic assay (ELISA) with monoclonal antibodies against the P. falciparum histidine‐rich protein (HRP2), expressed by the erythrocytic forms. The plant roots showed the lowest IC50 value and displayed the lowest toxicity, thus having the best therapeutic index. C. pachystachya species is therefore a good candidate for phytotherapeutic use against malaria. Further studies are ongoing to isolate new active compounds through bioguided fractionation analysis, in an effort to develop a new drug prototype against P. falciparum erythrocytic parasites. Drug Dev Res 71: 82–91, 2010. © 2009 Wiley‐Liss, Inc.
Growth hormone and anabolic steroids: athletes are the tip of the iceberg
Authors: Perls Thomas T. 
Published: December 2009

AbstractProfessional Athletes' misuse of anabolic steroids, growth hormone and other drugs are the tip of a very large, mostly ignored iceberg, made up of people who receive these drugs for such non‐medical uses as body‐building, school sports and “anti‐aging”. Although these drugs are often used in combination, this article focuses on growth hormone. Fuelling the demand for these drugs are drug manufacturers, pharmacies, websites, clinics and their doctors. Copyright © 2009 John Wiley & Sons, Ltd.
Stimulus distinction in the skin of a robot using tactile and shock sensors
Authors: Fukushima Masanori , Masuda Ryosuke 
Published: December 2009

AbstractRecent developments in the areas of mobile and humanoid robots have resulted in a marked increase in the potential applications of robotics. Since it is likely that robots will cohabitate and interact with humans in a variety of situations, they will need an external skin capable of distinguishing between various stimuli. The present study investigates the development of robot‐skin sensors capable of recognizing four stimuli that are frequently encountered in everyday life. A prototype was designed using pressure‐sensitive rubber and two types of shock sensors, and results indicate that the four stimuli can be distinguished based on differences in pressure and acceleration between stimuli. We describe the development of the skin sensory system and the mechanism employed to distinguish between the different stimuli, and present the results of experiments conducted using the developed system. © 2009 Wiley Periodicals, Inc. Electron Comm Jpn, 93(1): 50–57, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecj.10103
Quasi multi‐baseline‐stereo method with single camera for reducing occlusion
Authors: Watanabe Takashi , Kusano Akira , Fujiwara Takayuki , Koshimizu Hiroyasu 
Published: December 2009

AbstractA robust 3D image measurement method is proposed in order to suppress occlusion by a quasi multi‐baseline‐stereo method based on a single camera configuration. There is no way to suppress completely the “occlusion problem” in the field of stereo geometry. In order to deal with this problem, the multi‐baseline‐stereo configuration is often adopted and is basically effective. This paper proposes a new configuration for stereo measurement by means of a single camera, a mechanical feeder for the object, image processing for the baseline calibration, and in particular, diagonal feeding of the object in front of the camera. The concept of this method is to realize a pair of stereo geometries in the stereo configuration with a single camera and a mechanical feeder. It is technically noted that the baseline of this single camera stereo was precisely calibrated by an image processing procedure in both the horizontal and vertical directions. © 2009 Wiley Periodicals, Inc. Electron Comm Jpn, 93(1): 41–49, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecj.10156
Analysis and modeling of practical experiment on IP traffic control
Authors: Suzuki Tadamichi , Ito Jungo , Nakano Kazushi , Miki Tetsuya 
Published: December 2009

AbstractIn this paper, we focus on a practical experiment concerning IP traffic engineering over Multi‐Protocol Label Switching (MPLS), especially which features feedback control capabilities. We present control‐theoretic analysis of the experimental results based on acquired knowledge of actual network behavior. Because stable automated control capabilities are key issues in IP traffic engineering, we model an IP traffic control system based on the resulting analysis. In addition, comparison between simulated network behavior and actual behavior shows this model to have a high degree of stability, with a high potential for application to real networks. © 2009 Wiley Periodicals, Inc. Electron Comm Jpn, 93(1): 9–18, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecj.10189
Cytotoxicity test and mass spectrometry of IPMC
Authors: Takashima Kazuto , Kamamichi Norihiro , Yagi Tohru , Asaka Kinji , Mukai Toshiharu 
Published: December 2009

AbstractIonic polymer‐metal composites (IPMC) are promising materials in biomedical actuators and sensors, as they are soft and flexible, thus assuring the safety of the device itself. The purpose of this study is to investigate the biocompatibility of IPMC in in vitro experiments in order to evaluate their applicability in biomedical fields. In addition to an IPMC specimen prepared by the conventional “impregnation‐reduction method” using cationic gold complexes and reducing agents, two specimens were prepared by additional processes: one specimen was reduced in Na2SO3 solution and the other was cleaned in H2O2 solution. A colony‐forming test using Chinese hamster V79 cells showed high cytotoxicity for all IPMC specimens. Examination by direct inlet mass spectrometry (DI‐MS) revealed that the peak intensity of the gold complex (particularly, m/z=180) was different from that of Nafion film. Monitoring the peak at m/z=180 showed a remnant with the structure of phenanthroline in IPMC specimens that were not cleaned in H2O2 solution. © 2009 Wiley Periodicals, Inc. Electron Comm Jpn, 93(1): 1–8, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecj.10239
Preparation of Carbocyclic C‐Nucleosides from α‐Chlorooxime Precursor
Authors: Pradere Ugo , Kumamoto Hiroki , Roy Vincent , Agrofoglio Luigi A. 
Published: December 2009

AbstractThe syntheses of L‐carbocyclic benzothiazolo, benzoxazolo, and benzimidazolo C‐nor‐nucleosides are described. The key step is the reaction of the C‐chlorooxime 7, obtained by C‐chlorination with N‐chlorosuccinimide of [(1S,2R,3R,4R)‐1‐tert‐butyldimethylsiloxy‐2,3‐(O‐isopropylidenedioxy)]cyclopentane‐4‐carbohydroximic acid (6), with different α‐amino aromatic compounds. Acidic deprotection gave the benzoxazolo (11), benzimidazolo (12), and benzothiazolo (13) title compounds, in good yields.
How do bedform patterns arise? New views on the role of bedform interactions within a set of boundary conditions
Authors: Kocurek Gary , Ewing Ryan C. , Mohrig David 
Published: December 2009

AbstractOne explanation for bedform patterns is self‐organization in which the pattern emerges because of interactions among the bedforms themselves. Models, remote images, field studies and lab experiments have identified bedform interactions that involve whole bedforms, only bedform defects, or that are remote interactions between bedforms. It is proposed that bedform interactions form a spectrum from constructive to regenerative in pattern development. Constructive interactions, including merging, lateral linking, cannibalization, and remote transfer of sediment, push the system toward fewer, larger, more widely spaced bedforms. Regenerative interactions, including bedform splitting, defect creation and calving, push the system back toward a more initial state. Other interactions, including off‐center collision, defect migration, and bedform and defect repulsion, cause pattern change, but may not be strongly constructive or regenerative. Although bedform interactions are ubiquitous to any field of bedforms, their dynamics, flow‐field modification, and impact upon measurable pattern parameters are yet poorly understood. Most bedform interactions span bedform types and fluids, supporting the hypothesis that pattern emerges from dynamics at the bedform level in a hierarchy that includes lower levels of bedform‐flow and grain–fluid interactions. Bedform interactions alone, however, cannot account for the rich diversity of bedform patterns in nature. It is proposed that field diversity arises because of boundary conditions, which are the environmental variables within which a field evolves. Conceptually, boundary conditions modify the shape of the attractor toward which a field evolves, possibly by altering the type and frequency of bedform interactions. Boundary conditions are broadly similar within system types, but are unique for each bedform field so that no two are ever exactly alike. Although aeolian and fluvial systems share some types of boundary conditions, flow depth is a unique boundary condition in shallow fluvial systems. Copyright © 2009 John Wiley & Sons, Ltd.
Forecasting inflation in Malaysia
Authors: Duasa Jarita , Ahmad Nursilah , Ibrahim Mansor H. , Zainal Mohd Pisal 
Published: December 2009

AbstractThis paper aims to identify the best indicator in forecasting inflation in Malaysia. In methodology, the study constructs a simple forecasting model that incorporates the indicator/variable using the vector error correction (VECM) model of quasi‐tradable inflation index and selected indicators: commodity prices, financial indicators and economic activities. For each indicator, the forecasting horizon used is 24 months and the VECM model is applied for seven sample windows over sample periods starting with the first month of 1980 and ending with the 12th month of every 2 years from 1992 to 2004. The degree of independence of each indicator from inflation is tested by analyzing the variance decomposition of each indicator and Granger causality between each indicator and inflation. We propose that a simple model using an aggregation of indices improves the accuracy of inflation forecasts. The results support our hypothesis. Copyright © 2009 John Wiley & Sons, Ltd.