bluuebunny/crossref_metadata_2025 huggingface dataset:
Recent Advances in the Study of the Bioactive Conformation of Taxol
Authors: Sun Liang , Simmerling Carlos , Ojima Iwao
Published: April 2009

Demystifying Taxol: The structurally complex natural product paclitaxel is among the most important antitumor drugs presently in the clinic. While the mechanism of action is known, the biologically active conformation has been much debated. Herein we summarize the considerable research efforts that have gone into elucidating the bioactive conformation of paclitaxel.

magnified image

Paclitaxel is one of the most important chemotherapeutic drugs in the fight against cancer. This minireview covers the recent advances in the study of the bioactive conformation of paclitaxel in tubulin/microtubules. The tubulin‐bound structure of paclitaxel has been studied by means of photoaffinity labeling, cryo‐electron microscopy, solid‐state NMR, molecular modeling, MD simulations and the synthesis of conformationally restrained analogues and paclitaxel mimics. The bioactive conformation of paclitaxel is important since it could provide critical information that would allow the design of novel analogues with simpler structures and/or increased potency against cancer.
Tensor products and correlation estimates with applications to nonlinear Schrödinger equations
Authors: Colliander James , Tzirakis Nikolaos , Grillakis Manoussos G.
Published: April 2009

We prove new interaction Morawetz‐type (correlation) estimates in one and two dimensions. In dimension 2 the estimate corresponds to the nonlinear diagonal analogue of Bourgain's bilinear refinement of Strichartz. For the two‐dimensional case we provide a proof in two different ways. First, we follow the original approach of Lin and Strauss but applied to tensor products of solutions. We then demonstrate the proof using commutator vector operators acting on the conservation laws of the equation. This method can be generalized to obtain correlation estimates in all dimensions. In one dimension we use the Gauss‐Weierstrass summability method acting on the conservation laws. We then apply the two‐dimensional estimate to nonlinear Schrödinger equations and derive a direct proof of Nakanishi's H1 scattering result for every L2‐supercritical nonlinearity. We also prove scattering below the energy space for a certain class of L2‐supercritical equations. © 2009 Wiley Periodicals, Inc.
Optical Spectroscopic Methods for Probing the Conformational Stability of Immobilised Enzymes
Authors: Ganesan Ashok , Moore Barry D. , Kelly Sharon M. , Price Nicholas C. , Rolinski Olaf J. , Birch David J. S. , Dunkin Ian R. , Halling Peter J.
Published: April 2009

Structure of immobilised enzymes: Circular dichroism, infrared and fluorescence spectroscopic methods are used to characterise in situ structural stability of enzymes immobilised on particles. The enzyme subtilisin Carlsberg exhibits a similar secondary structure in solution and in the immobilised state but on the surface of porous silica gel a rigid tertiary structure is preferred (see picture).

magnified image

We report the development of biophysical techniques based on circular dichroism (CD), diffuse reflectance infrared Fourier transform (DRIFT) and tryptophan (Trp) fluorescence to investigate in situ the structure of enzymes immobilised on solid particles. Their applicability is demonstrated using subtilisin Carlsberg (SC) immobilised on silica gel and Candida antartica lipase B immobilised on Lewatit VP.OC 1600 (Novozyme 435). SC shows nearly identical secondary structure in solution and in the immobilised state as evident from far UV CD spectra and amide I vibration bands. Increased near UV CD intensity and reduced Trp fluorescence suggest a more rigid tertiary structure on the silica surface. After immobilised SC is inactivated, these techniques reveal: a) almost complete loss of near UV CD signal, suggesting loss of tertiary structure; b) a shift in the amide I vibrational band from 1658 cm−1 to 1632 cm−1, indicating a shift from α‐helical structure to β‐sheet; c) a substantial blue shift and reduced dichroism in the far UV CD, supporting a shift to β‐sheet structure; d) strong increase in Trp fluorescence intensity, which reflects reduced intramolecular quenching with loss of tertiary structure; and e) major change in fluorescence lifetime distribution, confirming a substantial change in Trp environment. DRIFT measurements suggest that pressing KBr discs may perturb protein structure. With the enzyme on organic polymer it was possible to obtain near UV CD spectra free of interference by the carrier material. However, far UV CD, DRIFT and fluorescence measurements showed strong signals from the organic support. In conclusion, the spectroscopic methods described here provide structural information hitherto inaccessible, with their applicability limited by interference from, rather than the particulate nature of, the support material.
Redox Properties of Mixed Lutetium/Yttrium Nitride Clusterfullerenes: Endohedral LuxY3−xN@C80(I) (x=0–3) Compounds
Authors: Tarábek Ján , Yang Shangfeng , Dunsch Lothar
Published: April 2009

The complex redox behavior of mixed lutetium/yttrium nitride clusterfullerenes of the series LuxY3−xN§C80(Ih, x=0–3) (see figure) results in up to three irreversible reduction steps. A reduction mechanism is proposed based on fast‐scan and square‐wave voltammetry experiments combined with simulations of the voltammograms.

magnified image

The redox behavior of mixed lutetium/yttrium nitride clusterfullerenes of the series LuxY3−xN@C80(Ih, x=0–3) is studied for the first time by means of cyclic voltammetry, fast‐scan cyclic voltammetry, square‐wave voltammetry, and electron paramagnetic resonance (EPR) spectroelectrochemistry. A reversible single‐electron‐transfer process, which does not result in an EPR signal, is detected during the anodic oxidation sweep of cyclic voltammetry experiments performed at different temperatures (296 and 360 K). The cathodic reduction sweep reveals a rather complex response for all the four clusterfullerenes—with up to three irreversible reduction steps. By correlating the results of fast‐scan and square‐wave voltammetry and combining them with simulations of the voltammograms, we are able to propose a reduction mechanism for the LuxY3−xN@C80(I) (x=0–3) fullerenes.
Microhardness studies on as‐grown (111) faces of some alkaline earth nitrates
Authors: Shekar P. V. Raja , Nagaraju D. , Ganesh V. , Rao K. Kishan
Published: April 2009

Single crystals of Sr(NO3)2, Ba(NO3)2 and Pb(NO3)2 are grown from their aqueous solutions at a constant temperature of 35 °C by slow evaporation technique. Crystals of size 8 to 10 mm along one edge are obtained in a period of 10 days. Chemical etching technique has been employed to study the dislocations in these crystals. The dislocations are randomly distributed and the dislocation density is about 104 to 105 /cm2. Microhardness studies are made on as–grown (111) faces of these crystals upto a load of 100 g. The hardness of the crystals increases with an increase in load and thereafter it becomes independent of the applied load. These results are discussed on the basis of reverse indentation size effect. Meyer index number n for these crystals is estimated at both low and high load regions. An analysis of hardness data of these crystals as well as some other cubic crystals like alums and alkali halates are discussed using Gilman–Chin parameter Hv/C44, where Hv is the microhardness and C44 is the shear constant. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Catalytic Processing of Lactic Acid over Pt/Nb2O5
Authors: Serrano‐Ruiz Juan Carlos , Dumesic James A.
Published: April 2009

Aqueous solutions of lactic acid derived from biomass can be catalytically upgraded over Pt(0.1 %)/Nb2O5 into an organic phase rich in C4–C7 ketones that spontaneously separates from water. The single‐reactor process retains 50 % of the feed carbon in the organic layer. The niobia support catalyzes CC coupling reactions and plays a key role in directing the synthesis towards these valuable products.

magnified image

Dilute aqueous solutions of lactic acid (30 %wt.) can be catalytically processed at 573 K and 57 bar over a low‐metal‐content Pt(0.1 %)/Nb2O5 catalyst in a spontaneously separating organic phase rich in valuable products such as C4–C7 ketones. An increase in the lactic acid concentration to 60 wt % allows conversion of approximately 50 % of the carbon feed in this organic layer, while maintaining good stability of the catalyst. Experiments at low conversion showed that lactic acid reacts first over Pt(0.1 %)/Nb2O5 to produce acetaldehyde and propanoic acid (along with CO and CO2 in the gas phase). These compounds (less oxygenated than lactic acid but still reactive) are the key intermediates in the overall process, and they react differently depending on the nature of the catalyst support. In particular, reaction kinetics studies with propanoic acid as feed showed that Pt(0.1 %)/Nb2O5 favored the formation of pentanones by ketonization reactions, whereas a monofunctional Pt(0.1 %)/carbon catalyst produced ethane and COx by decomposition reactions. In the same manner, acetaldehyde was preferentially hydrogenated to ethanol over Pt(0.1 %)/carbon, whereas the presence of niobia allowed this intermediate to react (by successive aldol condensations) to form C4–C7 condensation products stored in the organic phase. Finally, reaction pathways are proposed to explain the catalytic processing of lactic acid over bifunctional Pt(0.1 %)/Nb2O5. In this scheme, metal sites catalyze hydrogenation reactions and niobia promotes CC coupling processes (ketonization and aldol condensation), in contrast to CC cleavage reactions which take place preferentially over Pt(0.1 %)/carbon and lead to loss of carbon in the gas effluent as CO, CO2, and methane.
Carbons and Carbon‐Supported Catalysts in Hydroprocessing.Edited by Edward Furimsky
Authors: Sertic‐Bionda Katica
Published: April 2009

Royal Society of Chemistry, Cambridge, 2008. 150 pp., hardcover € 130.99.—ISBN 978‐0‐85404‐143‐5

magnified image
Iron Catalysis in Organic Chemistry.Edited by Bernd Plietker
Authors: Renaud Jean‐Luc
Published: April 2009

Wiley‐VCH, Weinheim, 2008. 295 pp., hardcover € 149.00—ISBN 978‐352‐731927‐5

magnified image
Developmental shifts in gene expression in the auditory forebrain during the sensitive period for song learning
Authors: London Sarah E. , Dong Shu , Replogle Kirstin , Clayton David F.
Published: April 2009

A male zebra finch begins to learn to sing by memorizing a tutor's song during a sensitive period in juvenile development. Tutor song memorization requires molecular signaling within the auditory forebrain. Using microarray and in situ hybridizations, we tested whether the auditory forebrain at an age just before tutoring expresses a different set of genes compared with later life after song learning has ceased. Microarray analysis revealed differences in expression of thousands of genes in the male auditory forebrain at posthatch day 20 (P20) compared with adulthood. Furthermore, song playbacks had essentially no impact on gene expression in P20 auditory forebrain, but altered expression of hundreds of genes in adults. Most genes that were song‐responsive in adults were expressed at constitutively high levels at P20. Using in situ hybridization with a representative sample of 44 probes, we confirmed these effects and found that birds at P20 and P45 were similar in their gene expression patterns. Additionally, eight of the probes showed male–female differences in expression. We conclude that the developing auditory forebrain is in a very different molecular state from the adult, despite its relatively mature gross morphology and electrophysiological responsiveness to song stimuli. Developmental gene expression changes may contribute to fine‐tuning of cellular and molecular properties necessary for song learning. © 2009 Wiley Periodicals, Inc. Develop Neurobiol 2009
Analysis of affective factors of colored three‐dimensional shapes
Authors: Miura Takeshi , Matsuo Kenshi , Taniguchi Toshiyuki
Published: April 2009

“Shape” has been regarded as one of the fundamental elements of plastic art, together with “color” and “material.” The purpose of this paper is to investigate the influence of shape on affective meanings, when the visual stimulus is a three‐dimensional shape. The semantic differential technique is used for the extraction of affective factors, with samples of stimuli produced by three‐dimensional computer graphics (3DCG). Since it is difficult to separate the stimuli of shape and color in the visual stimulus of a three‐dimensional shape, both single‐color experiments and colored three‐dimensional‐shape experiments were performed; the influence of shape is investigated by comparison of the respective results. A total of 33 single colors and 132 colored three‐dimensional shapes with simple geometrical form (cube, cylinder, cone, and sphere) were used as samples.

Four factors are extracted for single‐color stimuli by factor analysis: “showiness,” “pleasantness,” “strength,” and “warmth.” The factor of “looseness” is also added to the above factors in the case of a three‐dimensional‐shape stimulus. The following tendencies of these factors are obtained: among the single‐color factors, the factors of “pleasantness” and “warmth” show marked variation caused by the influence of shape, and the factor score of “looseness” depends on the straightness or roundness of the shape. © 2009 Wiley Periodicals, Inc. Electron Comm Jpn, 92(5): 41–54, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecj.10001
Computer input system based on gaze vector estimation with iris center detection from face images acquired with a Web camera allowing user movement
Authors: Arai Kohei
Published: April 2009

A system which allows computer input without a keyboard is proposed. The system utilizes a display‐mounted Web camera for acquisition of the user's face and also a display‐mounted lamp for illumination of the user. It is found that the proposed system allows almost perfect computer input (90%) if the distance between the user and display is within 30 cm and if the keyboard image is displayed on a 19‐inch computer display (8‐cm key distance) with 40‐W fluorescent light as normal illumination from both sides of the display. The proposed system thus requires one retry of key entry in ten times. The proposed system allows user movement, because a moving picture of the user's face is acquired in real time. The relation of the allowable user movement to the success rate, and the relation of the signal‐to‐noise ratio and the contrast of the acquired image of the user to the success rate are determined. © 2009 Wiley Periodicals, Inc. Electron Comm Jpn, 92(5): 31–40, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecj.10015
Development research on high‐performance ultrasound sensor system
Authors: Okugumo Masaki , Kimura Akihiko , Ohki Makoto , Ohkita Masaaki
Published: April 2009

Ultrasound sensor systems are widely used in various fields such as external environment sensors for autonomous mobile robots, mainly due to their features, small size, and easy construction. However, the conventional ultrasound sensor system is limited to measuring only the distance to the object at the time of reflection of the ultrasound wave. In this paper, a new type of high‐performance ultrasound sensor system is proposed. In this system, an ultrasound wave modulated by several featured frequencies is transmitted and the reflected waves are analyzed by means of the Fourier transform. At the same time, the system can measure the speed, the direction of the movement, and the surface ruggedness of the object. The effectiveness of the proposed system is demonstrated through experimental results. © 2009 Wiley Periodicals, Inc. Electron Comm Jpn, 92(5): 23–30, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecj.10034
A new decomposition system for volatile organic compounds using combinations of dielectric barrier discharges with zeolite honeycomb sheets
Authors: Inoue Koji , Furuki Keimei , Okano Hiroshi , Yamagata Yukihiko , Muraoka Katsunori
Published: April 2009

A new decomposition system for volatile organic compounds (VOCs), based on dielectric barrier discharges combined with zeolite honeycomb sheets, has been developed. A discharge element was made of layered flat metal sheets covered with mica sheets separated by 2 mm, in which corrugated (honeycomb‐shaped) ceramic sheets embedded with zeolites were inserted. This element was shown to satisfy the requirements of durability and flexibility to meet various sizes. Barrier discharges were investigated using this discharge element over wide ranges of operating conditions, in terms of the power consumption and decompositions of various types of VOCs. By selecting suitable operating scenarios, it was found that decomposition of more than 90% of most VOCs was possible, at reasonable power consumption and without electrode contamination by decomposition products. Finally, areas of competitive applications of the present system versus existing decomposition systems are also dicussed. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 168(1): 1–10, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20736
A new unified analysis of estimate errors by model‐matching phase‐estimation methods for sensorless drive of permanent magnet synchronous motors and new trajectory‐oriented vector control, Part I
Authors: Shinnaka Shinji , Sano Kousuke
Published: April 2009

This paper presents a new unified analysis of estimate errors by model‐matching phase estimation methods such as rotor‐flux state observers, back EMF state observers, and back EMF disturbance observers, for sensorless drive of permanent magnet synchronous motors. Analytical solutions for estimate errors, whose validity is confirmed by numerical experiments, are rich in universality and applicability. As an example of universality and applicability, a new trajectory‐oriented vector control method is proposed, which can directly realize quasi‐optimal strategy minimizing total losses with no additional computational loads by simply orienting one of the vector‐control coordinates to the associated quasi‐optimal trajectory. The coordinate orientation rule, which is analytically derived, is surprisingly simple. Consequently, the trajectory‐oriented vector control method can be applied to a number of conventional vector control systems using one of the model‐matching phase estimation methods. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 168(1): 52–65, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20801
A new unified analysis of estimate errors by model‐matching phase‐estimation methods for sensorless drive of permanent‐magnet synchronous motors and new trajectory‐oriented vector control, Part II
Authors: Shinnaka Shinji
Published: April 2009

This paper presents a new unified analysis of estimate errors by model‐matching extended‐back‐EMF estimation methods for sensorless drive of permanent‐magnet synchronous motors. Analytical solutions for estimate errors, whose validity is confirmed by numerical experiments, are rich in universality and applicability. As an example of their universality and applicability, a new trajectory‐oriented vector control method is proposed, which can realize directly a quasi‐optimal strategy minimizing total losses with no additional computational loads by simply orienting one of the vector‐control coordinates to the associated quasi‐optimal trajectory. The coordinate orientation rule, which is analytically derived, is surprisingly simple. Consequently, the trajectory‐oriented vector control method can be applied to a number of conventional vector control systems using model‐matching extended‐back‐EMF estimation methods. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 168(1): 66–78, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20802
Partial discharge degradation of several biodegradable polymers
Authors: Fuse Norikazu , Fujita Shinjiro , Hirai Naoshi , Tanaka Toshikatsu , Kozako Masahiro , Kohtoh Masanori , Okabe Shigemitsu , Ohki Yoshimichi
Published: April 2009

Partial discharge (PD) resistance was examined by applying a constant voltage to four different biodegradable polymers—poly‐L‐lactic acid (PLLA), polyethylene terephthalate succinate (PETS), poly ε‐caprolactone butylene succinate (PCL‐BS), and polybutylene succinate (PBS)—and the results were compared with those of low‐density polyethylene (LDPE) and crosslinked low‐density polyethylene (XLPE). The PD resistance is determined by the erosion depth and the surface roughness caused by PDs, and is ranked as LDPE≈XLPE>PLLA≈PETS>PBS>PCL−BS. This means that the sample with a lower permittivity has better PD resistance. Furthermore, examination of the sample surfaces by a polarization microscope and a laser confocal microscope reveals that the PD resistance of crystalline regions with spherulites is higher than that of amorphous regions. Therefore, good PD resistance can be achieved by the sample with a high crystallinity and a low permittivity. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 168(2): 1–10, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20807
Gene expression after dietary intervention with trans fatty acids (trans‐11/trans‐12 18:1) in humans
Authors: Kuhnt Katrin , Flotho Silke , Benjamin Sailas , Boerchers Torsten , Schubert Rainer , Jahreis Gerhard , Spener Friedrich
Published: April 2009

Gene‐by‐diet interactions play an important role in the prevention of several diseases. Conjugated linoleic acids (CLA) are ligands of gene regulators [e.g. peroxisome proliferator‐activated receptors (PPAR)] and have anti‐inflammatory properties. The aim of the study was to investigate the changes in gene expression in monocytes during the intervention with two trans fatty acids (trans‐11 18:1 and trans‐12 18:1) and endogenous CLA from trans‐11 18:1 as precursor in humans. Monocytes were isolated at baseline and after a 6‐week intervention period. The female and male test groups received Σ6.0 g trans‐11 and trans‐12 18:1/day (1 : 1). The control group received control oil. The expression of candidate genes was determined by quantitative RT‐PCR. Gender‐ and treatment‐related gene expression was found. Due to trans fatty acid intake in both gender subgroups, the relative PPARγ expression was up‐regulated. In the female test group, the expression of FAT, SCD, COX2 and BCL2 were induced, while in the male test group E‐FABP, CYP, GLUT4 and PBE were induced. In the male test group compared to controls, a clear increase in gene expression of PPARγ and GLUT4 was shown. The results reveal a gender‐ and treatment‐related gene expression. There is no clear indication as to what extent the supplemented trans fatty acids and the synthesized cis‐9,trans‐11 CLA were involved.
Modified cyclodextrins for fast and sensitive chiral‐capillary electrophoresis‐mass spectrometry
Authors: Giuffrida Alessandro , León Carlos , García‐Cañas Virginia , Cucinotta Vincenzo , Cifuentes Alejandro
Published: April 2009

In this work, three modified CDs (mCDs), namely 6‐deoxy‐6‐[1‐(2‐amino)ethylamino]‐β‐CD, 6‐deoxy‐6‐[N‐(2‐methylamino)pyridine)]‐β‐CD and 3‐monodeoxy‐3‐monoamino‐β‐CD, are investigated as chiral selectors for CE with LIF (CE‐LIF) and CE‐TOF‐MS. The potential of these three mCDs as chiral selectors in CE was also compared with the unmodified β‐CD and γ‐CD. A group of ten different D‐ and L‐amino acids derivatized with FITC was selected as case‐study for CE‐LIF and CE‐MS comparison. The analyte group includes negatively (D/L‐Glu and D/L‐Asp), neutral (D/L‐Ala and D/L‐Asn) and positively (D/L‐Arg) charged amino acids. Chiral separation conditions compatible with CE‐TOF‐MS could be achieved based on the figures of merit obtained by CE‐LIF using the different CDs. Interestingly, LOD values obtained by chiral CE‐TOF‐MS were in the nM range comparable or only slightly worse to those obtained by CE‐LIF. Moreover, the time of analysis using mCDs was reduced more than 30% compared with the non‐chiral conditions (19.2 versus 28.4 min, respectively), with resolution and efficiency values as high as 5.15 and 843 000 plates/m, respectively. The usefulness of this chiral CE‐TOF‐MS method was corroborated through the detection of the main D‐ and L‐amino acids found in different real samples including transgenic versus wild soy and vinegar.
Analysis of aristolochic acids by CE‐MS with carboxymethyl chitosan‐coated capillary
Authors: Fu Xiaofang , Liu Yi , Li Wei , Pang Nannan , Nie Honggang , Liu Huwei , Cai Zongwei
Published: April 2009

A CE‐MS method for rapid determination of aristolochic acid‐I and aristolochic acid‐II (AA‐II) in traditional Chinese medicines and biological samples was described in the present paper. AA‐I and AA‐II can be baseline separated within 6 min by CE‐MS with carboxymethyl‐chitosan‐coated capillary. CZE conditions including pH, concentration of buffer, applied voltage, and capillary temperature were systematically investigated, and the composition and flow rate of sheath liquid were also optimized for CE‐MS. Furthermore, the CE‐UV method without any additives in BGE solution was established and compared with the CE‐MS method. The results showed that the two methods could achieve satisfactory separation efficiency, repeatability, and linearity, while the LOD was 0.6 μg/mL for CE‐UV and 0.05 μg/mL for CE‐MS. Compared with the CE‐UV method, the sensitivity of CE‐MS was significantly improved, in addition to the structure information provided by MS detection at the same time. As an application example, a spiked sample in human serum was analyzed by the CE‐MS method, indicating that the new CE‐MS method can be applied to analyze AAs in biological samples.
Direct automatic determination of free and total anesthetic drugs in human plasma by use of a dual (microdialysis–microextraction by packed sorbent) sample treatment coupled at‐line to NACE–MS
Authors: Morales‐Cid Gabriel , Cárdenas Soledad , Simonet Bartolomé M. , Valcárcel Miguel
Published: April 2009

This paper reports for the first time the use of microextraction by packed sorbent in combination with CE. The combined system was used to determine anesthetic drugs in human plasma. A microdialysis fiber was coupled on‐line to the microextraction unit in order to distinguish between free and total concentrations of drugs. The system was automated by connecting the microextraction unit to a syringe pump and interfacing it to a computer. The ensuing method allows the determination of 10 μg/L concentrations of free drugs and 1 μg/L concentrations of total drugs from only 200 μL of sample with an RSD of less than 9%.
Recent food safety and food quality applications of CE‐MS
Authors: Ravelo‐Pérez Lidia M. , Asensio‐Ramos María , Hernández‐Borges Javier , Rodríguez‐Delgado Miguel Ángel
Published: April 2009

The first on‐line coupling of CE with MS detection more than 20 years ago provided a very powerful technique with a wide variety of applications, among which food analysis is of special interest, especially that dealing with food safety and food quality applications, the major topics of public interest nowadays. With this review article, we would like to show the most recent applications of CE‐MS in both fields by recompiling and commenting articles published between January 2004 and October 2008. Although both applications are difficult to separate from each other, we have included in this work two main sections dealing with each specific field. Future trends will also be discussed.
Packet scheduling algorithms for optical packet switch with shared WDM buffers
Authors: Yang Junjie
Published: April 2009

In this paper, a buffer control strategy called limited greedy mode (LGM) is presented to handle fibre delay line (FDL) contentions which often occur in optical packet switch with shared FDL‐buffer. In order to make full use of the FDL‐buffer, three scheduling algorithms based on the LGM, i.e. Shortest Queue Based on Limited Greedy Mode (SQLGM), Increasing Queue Based on Limited Greedy Mode (IQLGM) and Shortest Queue Considering Output Void (SQCOV) are proposed. Performances of these three algorithms are evaluated by simulation experiments. Simulation results show that the SQCOV achieves the best performance. In addition, the buffering performance of shared FDL‐buffer also depends on the greedy degree of LGM and the granularity of FDL. Copyright © 2009 John Wiley & Sons, Ltd.
Flame spread measurements on wood products using the ASTM E 1321 LIFT apparatus and a reduced scale adaptation of the cone calorimeter
Authors: Merryweather G. , Spearpoint M. J.
Published: April 2009

Flame spread experiments were conducted in an ASTM E 1321 lateral ignition and flame transport (LIFT) apparatus and a reduced scale ignition and flame spread test (RIFT) adaptation of the cone calorimeter. Wood‐based products were tested and a flame spread model was applied to the results to obtain the flame spread parameter and the minimum heat flux required for flame spread. The materials used were plywood, medium density fibreboard, hardboard, two‐particle board products, Melamine (Melteca) covered products with two types of wood substrate along with New Zealand grown Rimu, Beech, Macrocarpa and Radiata Pine. The RIFT gave comparable results to the LIFT for several of the materials investigated. There appeared to be an effective limit on suitable materials that can be successfully tested in the RIFT to those that have a minimum flux for flame spread of less than 7kW/m2. This limitation was due to the rapid decay of the heat flux profile along the sample and the lower resolution dictated by the smaller size of the RIFT apparatus. It was found that the limit on the minimum heat flux for flame spread was approximately equivalent to a minimum ignition flux of 18kW/m2. Copyright © 2009 John Wiley & Sons, Ltd.
Beyond six scents: defining a seventh Thymus vulgaris chemotype new to southern France by ethanol extraction
Authors: Keefover‐Ring Ken , Thompson John D. , Linhart Yan B.
Published: April 2009

The concept of plant chemotype has long been useful to describe secondary chemical phenotypes; however, the idea has practical limitations, especially when applied to ecological questions. This work reports the discovery of a new 1,8‐cineole chemotype of Thymus vulgaris from a well‐studied area in southern France. Multivariate statistical analysis of ethanol‐extracted plant terpenes was used to describe this new chemotype and three others found at the site, and the results are used to discuss the chemotype concept. While the total amount of essential oils among these chemotypes showed no difference, the concentration of the main terpene differed significantly, with the 1,8‐cineole and cis‐sabinene hydrate chemotypes having the lowest amounts of their respective main components, and the linalool chemotype having the highest. The α‐terpinyl acetate chemotype had intermediate levels of its main terpene. A factor analysis revealed four factors which explained almost 89% of the total variation in plant essential oils. Each factor represented a separate chemotype, including a cis‐sabinene hydrate, linalool, α‐terpinyl acetate and the new 1,8‐cineole chemotype. Although the concept of plant chemotype is still valid, better definitions are important when evaluating the influences of a plant's secondary chemistry on other community members. Copyright © 2009 John Wiley & Sons, Ltd.
Head and neck squamous cell carcinoma in FAMMM syndrome
Authors: Vinarsky Vladimir , Fine Robert L. , Assaad Adel , Qian Ying , Chabot John A. , Su Gloria H. , Frucht Harold
Published: April 2009

Background

Germline mutations at the INK4a/p16 locus are implicated in several human cancer syndromes, including familial atypical multiple mole melanoma (FAMMM) syndrome, FAMMM‐pancreatic cancer (FAMMM‐PC) syndrome, and in familial head and neck cancer syndrome.

Methods

We present an individual with a family history of melanoma and pancreatic cancer who had multiple dysplastic nevi, squamous cell carcinoma of the tongue at age 22, multiple melanomas, a second squamous cell cancer of the tongue at age 40, and ultimately a pancreatic cancer.

Results

We demonstrate a germline mutation in INK4a and loss of heterozygosity at this locus in his HNSCC tissue.

Conclusions

This report suggests that INK4a germline mutations associated with FAMMM/FAMMM‐PC can also be associated with HNSCC. We conclude that HNSCC in young individuals should prompt clinicians to obtain a family history and consider that the patient may have a germline p16 defect that could predispose them to other cancers, including melanoma and pancreatic cancer. © 2009 Wiley Periodicals, Inc. Head Neck, 2009
Hypothyroidism in older patients with head and neck cancer after treatment with radiation: A population‐based study
Authors: Smith Grace L. , Smith Benjamin D. , Garden Adam S. , Rosenthal David I. , Sherman Steven I. , Morrison William H. , Schwartz David L. , Weber Randal S. , Buchholz Thomas A.
Published: April 2009

Background

In patients with head and neck cancer, radiation treatment (RT) is a risk factor for hypothyroidism. However, the specific magnitude of risk after RT in older patients is not known.

Methods

We identified 5916 patients (age > 65 years) from SEER‐Medicare diagnosed with head and neck cancer from 1992 to 2002. Proportional hazards models compared hypothyroidism risk after any RT versus surgery alone.

Results

In patients treated with RT, 5‐year incidence of hypothyroidism was 20% and 10‐year incidence was 59%; in patients treated with surgery alone, incidence was 7% and 39% (p < .001). Patients treated with RT had increased adjusted risk (hazard ratio [HR] = 2.14; 95% confidence interval [CI] = 1.74–2.62), persisting for up to 10 years of follow‐up (HR = 1.85, 95% CI = 1.39–2.44 from 5 to 10 years).

Conclusion

In older patients with head and neck cancer, RT is associated with elevated hypothyroidism risk. As onset may be delayed for years, patients may require lifelong thyroid function screening after treatment. © 2009 Wiley Periodicals, Inc. Head Neck, 2009
EGFR protein overexpression and mutation in areca quid–associated oral cavity squamous cell carcinoma in Taiwan
Authors: Huang Shiang‐Fu , Chuang Wen‐Yu , Chen I‐How , Liao Chun‐Ta , Wang Hung‐Ming , Hsieh Ling‐Ling
Published: April 2009

Background.

Epidermal growth factor receptor (EGFR)‐targeted therapy has been extensively assessed in human cancer treatment. We appraised the possible role of tyrosine kinase inhibitors (TKIs) in areca quid (AQ)‐associated oral cavity squamous cell carcinomas (OSCCs) by examining EGFR protein overexpression and its tyrosine kinase domain mutations.

Methods.

EGFR overexpression was evaluated by immunohistochemical staining, and tyrosine kinase mutations was determined by direct sequencing of DNAs from 172 OSCC tumors.

Results.

Overexpression of EGFR was found in 27.9% (48 of 172) of the OSCCs and was associated with lymph node metastasis (p = .013) and extracapsular spread (p = .022). Only 1 (0.58%) OSCC displayed somatic EGFR mutation but in a silent form (T725T, ACG→ACA).

Conclusion.

EGFR‐targeted therapy might have some potential in AQ‐associated OSCCs for their EGFR frequently overexpressed, although EGFR mutations were rare. However, the feasibility of TKIs in AQ‐associated OSCCs needs further clinical testing. © 2009 Wiley Periodicals, Inc. Head Neck, 2009
Clinical and molecular features of mucosa‐associated lymphoid tissue (MALT) lymphomas of salivary glands
Authors: Toso Andrea , Aluffi Paolo , Capello Daniela , Conconi Annarita , Gaidano Gianluca , Pia Francesco
Published: April 2009

Background.

To analyze clinical features and to discuss the modality of investigation and treatment of a series of mucosa‐associated lymphoid tissue (MALT) lymphomas. To investigate the prevalence of aberrant promoter methylation, responsible for gene inactivation, in a selected panel of genes potentially involved in the pathogenesis of B‐cell malignancies as O6‐methylguanine‐DNA methyltransferase (MGMT), p73, death‐associated protein kinase (DAP‐k).

Methods.

Nine patients with primary MALT lymphoma of the salivary glands were retrospectively reviewed. MGMT, p73, DAP‐k apoptotic pathways were tested.

Results.

Methylation of DAP‐k was common (5/8; 63%). Histological examination ensured diagnostic confirmation, whereas fine‐needle aspiration cytology was not definitively diagnostic.

Conclusion.

Histological assessment is the gold standard in the diagnosis of salivary gland lesions. Parotidectomy represents a safe and reliable diagnostic tool leading to a definite diagnosis of MALT lymphomas in all cases and curative without other treatment in early‐stage MALT lymphoma. © 2009 Wiley Periodicals, Inc. Head Neck, 2009
Genetic polymorphisms in the tobacco smoke carcinogens detoxifying enzyme UGT1A7 and the risk of head and neck cancer
Authors: Lacko Martin , Roelofs Hennie M. J. , te Morsche Rene H. M. , Voogd Adri C. , Ophuis Michael B. Oude , Peters Wilbert H. M. , Manni Johannes J.
Published: April 2009

Background.

UGT1A7 is an enzyme involved in the metabolism of (pre)carcinogens present in tobacco smoke. We investigated whether genetic polymorphisms inUGT1A7, with predicted altered enzyme activity, may have a risk‐modifying effect on head and neck carcinogenesis.

Methods.

Blood samples from 427 patients with oral, pharyngeal, and laryngeal carcinoma and 420 healthy control subjects were investigated forUGT1A7polymorphisms. Based on these polymorphisms, patients and controls were divided according to predicted enzyme activity (low, intermediate, high).

Results.

Logistic regression analysis showed a significant increased distribution of predicted high activity UGT1A7 polymorphisms among the patients (OR:1.44; 95% CI: 1.07–1.93). Stratified analyses demonstrated that high activity UGT1A7 polymorphisms were even more significantly present in patients with laryngeal cancer, older patients, heavy smokers, and heavy drinkers when compared with the control subjects.

Conclusions.

Predicted high activity UGT1A7 polymorphisms were significantly associated with an increased risk of head and neck cancer. © 2009 Wiley Periodicals, Inc. Head Neck, 2009
Endoscopic nasopharyngectomy with potassium‐titanyl‐phosphate (KTP) laser for early locally recurrent nasopharyngeal carcinoma
Authors: Ko Jenq‐Yuh , Wang Cheng‐Ping , Ting Lai‐Lei , Yang Tsung‐Lin , Tan Ching‐Ting
Published: April 2009

Background.

Although early recurrent nasopharyngeal carcinoma (NPC) can be treated with surgery alone, conventional nasopharyngectomy still results in serious complications. Endoscopic nasopharyngectomy has been introduced, but data on the treatment outcomes of this technique are lacking.

Methods.

From March 2004 to December 2007, 28 patients with rT1 or rT2a NPC underwent potassium‐titanyl‐phosphate (KTP) laser nasopharyngectomy by endoscopic techniques with curative intent.

Results.

Twenty‐five patients underwent surgery alone. Only 3 patients received postoperative adjuvant therapy. The 2‐year local disease‐free and 2‐year overall survival rates for the 12 patients with rT1 tumor and for the 16 patients with rT2a tumor were 100% and 41.7% (p = .007); and 90.9% and 38.5% (p = .03), respectively. Only 3 patients had obvious osteonecrosis at the nasopharynx, and 1 patient developed hypoglossal nerve dysfuction.

Conclusions.

Endoscopic KTP laser nasopharyngectomy is a simple, safe, and successful procedure for treating rT1 NPC, though its benefits are less clear for rT2a. © 2009 Wiley Periodicals, Inc. Head Neck, 2009
Sequential egocentric strategy is acquired as early as allocentric strategy: Parallel acquisition of these two navigation strategies
Authors: Iglói Kinga , Zaoui Mohamed , Berthoz Alain , Rondi‐Reig Laure
Published: April 2009

At least two main cognitive strategies can be used to solve a complex navigation task: the allocentric or map‐based strategy and the sequential egocentric or route‐based strategy. The sequential egocentric strategy differs from a succession of independent simple egocentric responses as it requires a sequential ordering of events, possibly sharing functional similarity with episodic memory in this regard. To question the possible simultaneous encoding of sequential egocentric and allocentric strategies, we developed a paradigm in which these two strategies are spontaneously used or imposed. Our results evidenced that sequential egocentric strategy can be spontaneously acquired at the onset of the training as well as allocentric strategy. Allocentric and sequential egocentric strategies could be used together within a trial, and bidirectional shifts (between trials) were spontaneously performed during the training period by 30% of the participants. Regardless of the strategy used spontaneously during the training, all participants could execute immediate shifts to the opposite non previously used strategy when this strategy was imposed. Altogether, our findings suggest that subjects acquire different types of spatial knowledge in parallel, namely knowledge permitting allocentric navigation as well as knowledge permitting sequential egocentric navigation. © 2009 Wiley‐Liss, Inc.
Enhanced spatial memory and hippocampal long‐term potentiation in p75 neurotrophin receptor knockout mice
Authors: Barrett Graham L. , Reid Christopher A. , Tsafoulis Christina , Zhu Wenmei , Williams David A. , Paolini Antonio G. , Trieu Jennifer , Murphy Mark
Published: April 2009

Previous reports have described increases in the size and number of cholinergic neurons in the basal forebrain in p75 neurotrophin receptor (p75NTR) knockout mice. In an earlier study, we also found improved spatial memory in these mice, raising the possibility that p75NTR regulates hippocampal function by its effects on the cholinergic basal forebrain. We therefore investigated hippocampal long‐term potentiation in p75NTR knockout mice that shared the same genetic background as control 129/Sv mice. We also investigated heterozygous mice, carrying just one functional p75NTR allele. The p75NTR knockout mice had enhanced long‐term potentiation in the Schafer collateral fiber synapses of the hippocampus. Heterozygous mice had an intermediate level, greater than controls but less than knockout mice. Hippocampal choline acetyltransferase activity was also markedly elevated in p75NTR knockout mice, with a smaller increase in heterozygous mice. In the Barnes maze, p75NTR knockout mice displayed markedly superior learning to controls, and this was evident over the three age brackets tested. At each age, the performance of heterozygous mice was intermediate to the other groups. In the open field test, p75NTR knockout mice exhibited greater stress‐related behavioral responses, including freezing, than did control animals. There were no differences between the three groups in a test of olfactory function. The dose‐dependent effects of p75NTR gene copy number on hippocampal plasticity and spatial memory indicate that p75NTR has profound effects on hippocampal function. Bearing in mind that p75NTR is very sparsely expressed in the adult hippocampus and has a potent effect on hippocampal choline acetyltransferase activity, the effects of p75NTR on hippocampal function are likely to be mediated indirectly, by its actions on basal forebrain cholinergic neurons. © 2009 Wiley‐Liss, Inc.
The application of integrated urban inundation model in Republic of Korea
Authors: Kang Sang‐Hyeok
Published: April 2009

In urban areas with a high building density, features such as roads, buildings and river dykes significantly affect flow dynamics and flood propagation. This should therefore be accounted for in the model set‐up. While 2D hydraulic models of densely urban areas are at the forefront of current research into flood inundation mechanisms, these models are constrained by inadequate parameters of topography and insufficient data. In order to solve these problems, topographic information obtained from digital elevation model (DEM) is directly programmed into the urban inundation model for a densely urban area, without exchanging the input data. In this paper, the extraction of building area is described using a tight coupling approach within a GIS environment, and its influence on the extent of flood inundation with a high building density is estimated. Copyright © 2009 John Wiley & Sons, Ltd.
Analysis of the mechanical behavior of a titanium scaffold with a repeating unit‐cell substructure
Authors: Ryan Garrett , McGarry Patrick , Pandit Abhay , Apatsidis Dimitrios
Published: April 2009

Titanium scaffolds with controlled microarchitecture have been developed for load bearing orthopedic applications. The controlled microarchitecture refers to a repeating array of unit‐cells, composed of sintered titanium powder, which make up the scaffold structure. The objective of this current research was to characterize the mechanical performance of three scaffolds with increasing porosity, using finite element analysis (FEA) and to compare the results with experimental data. Scaffolds were scanned using microcomputed tomography and FEA models were generated from the resulting computer models. Macroscale and unit‐cell models of the scaffolds were created. The material properties of the sintered titanium powders were first evaluated in mechanical tests and the data used in the FEA. The macroscale and unit‐cell FEA models proved to be a good predictor of Young's modulus and yield strength. Although macroscale models showed similar failure patterns and an expected trend in UCS, strain at UCS did not compare well with experimental data. Since a rapid prototyping method was used to create the scaffolds, the original CAD geometries of the scaffold were also evaluated using FEA but they did not reflect the mechanical properties of the physical scaffolds. This indicates that at present, determining the actual geometry of the scaffold through computed tomography imaging is important. Finally, a fatigue analysis was performed on the scaffold to simulate the loading conditions it would experience as a spinal interbody fusion device. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 2009
Biomimetic sealant based on gelatin and microbial transglutaminase: An initial in vivo investigation
Authors: Liu Yi , Kopelman Doron , Wu Li‐Qun , Hijji Karam , Attar Ishay , Preiss‐Bloom Orahn , Payne Gregory F.
Published: April 2009

The potential of an in situ gel‐forming adhesive was examined as a hemostatic surgical sealant. The gel‐forming mechanism for this adhesive mimics the last stages of blood coagulation but uses nonblood proteins. Specifically, gelatin is used as the structural protein and a calcium‐independent microbial transglutaminase (mTG) is used as the crosslinking enzyme. In vitro burst pressure tests with porcine skin demonstrate that the gelatin‐mTG adhesive forms a gel within 30 min under moist conditions and this gel can restrain pressures of 200 mmHg. In vivo tests with a rat liver wound model showed that the gelatin‐mTG adhesive achieves complete hemostasis in 2.5 min and the gel (i.e., the biomimetic clot) offers substantial adhesive and cohesive strength. Complete hemostasis was also observed in 2.5 min after the gelatin‐mTG adhesive was applied to a briskly bleeding rat femoral artery wound. In a large animal porcine model, a femoral artery wound that resulted in extensive bleeding was sealed in 4 min by (i) clamping the artery for temporary hemostasis, (ii) removing excess blood, and (iii) applying the gelatin‐mTG adhesive. Thus, the biomimetic gelatin‐mTG adhesive may provide a simple, safe, and cost‐effective surgical sealant. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 2009