bluuebunny/crossref_metadata_2025 huggingface dataset:
Swelling kinetics of linseed oil‐based nanocomposites
Authors: Sharma Vinay , Banait J. S. , Kundu P. P.
Published: June 2009

The solvent‐resistance properties of the montmorillonite‐filled conjugated linseed oil‐based nanocomposites are studied in tetrahydrofuran through equilibrium swelling method at different temperatures. The values of “n” in solvent transport equation are found to be below “0.5,” showing the non‐Fickian diffusion in the polymer. The dependence of the diffusion coefficient on the composition, percentage of clay, and temperature has been studied for nanocomposite samples. The diffusion coefficient increases with an increase in the clay contents and temperature. The crosslink density of the nanocomposites ranges from 101.07 to 237.46 × 106 mol/cm3. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Modification of conductivity of P3HT by addition of endometallo fullerene
Authors: Roy Debmalya , Tripathi N. K. , Saraiya A. , Ram K.
Published: June 2009

Germanium endometallo fullerene was synthesized by arcing Ge‐impregnated graphite rod as anode and pure graphite rod as cathode. Photoluminescence (PL) and resistance measurements suggest that there are effective interactions at the interface of Ge endometallo fullerene and poly 3‐hexyl thiophene (P3HT). Four‐fold enhancement of conductance has been found by adding just one weight percentage of Ge endometallo fullerene in the P3HT matrix at room temperature. However, at lower and higher temperatures, the enhancement in conductivity is low compared with room temperature, indicating the efficient charge transfer across the interface at the temperature range of 300–350 K. Atomic force microscopy (AFM) images also confirm the fact that temperature makes the more ordered heterojunctions between P3HT and Ge endohedral metallofullerene, which, in turn, trigger charge separation across interfaces. A sharp quenching in PL intensity of P3HT at room temperature by adding Ge endometallo fullerene indicates a strong interaction between the two and this composite material can be useful in photovoltaic cell. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
A novel strategy to branched polyacrylonitrile via one‐pot RAFT copolymerization of acrylonitrile and an asymmetrical divinyl monomer
Authors: Liu Xiao‐Hui , Zhang Gui‐Bao , Li Bai‐Xiang , Bai Yun‐Gang
Published: June 2009

Branched polyacrylonitriles were prepared via the one‐pot radical copolymerization of acrylonitirle and an asymmetric divinyl monomer (allyl methacrylate) that possesses both a higher reactive methacrylate and a lower reactive allyl. RAFT technique was used to keep a low‐propagation chain concentration via a fast reversible chain transfer euilibration and thus the cross‐linking was prevented until a high level of monomer conversions. This novel strategy was demonstrated to engenerate a branched architecture with abundant pendant functional vinyl and nitrile groups, and controlled molecular weight as a behavior of controlled/living radical polymerization characteristics. The effect of the various experimental parameters, including temperature, brancher to monomer molar ratio, and chain transfer agent to initiator molar ratio, on the control of moleculer dimension (molecular weight and polydispersity indices) and the degree of branching were investigated in detail. Moreover, 1H NMR and gel permeation chromatography confirm the branched architecture of the resultant polymer. The intrinsic viscosity of the copolymer is also lower than the linear counterpart.© 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Studies on the atmospheric air–plasma treatment of PET (polyethylene terephtalate) woven fabrics: Effect of process parameters and of aging
Authors: Takke V. , Behary N. , Perwuelz A. , Campagne C.
Published: June 2009

The effect of process parameters and of aging on the atmospheric air–plasma treatment of polyethylene terephtalate (PET) woven fabric were studied using surface analysis methods: wettability/capillarity method as well as tapping mode atomic force microscopy imaging. Treatment time and plasma power have significant effect on the variation in fabric capillary weight, surface water contact angle and surface topography. Plasma treatment of PET surface with plasma species not only degrades the surface but also causes surface restructuring as the speed is lowered and the power is increased. An optimal treatment of the PET fabric samples, in terms of increased hydrophilicity both inside and on the PET fabric, is achieved at 60 KJ/m2 and at a lower speed of 1–2 m/min: water contact angle decreasing from 81° to 40° and capillary weight increasing from 55 to 380 mg. Aging experiments show that, the plasma‐treated surface is degraded to a more disordered structure without light, whereas in presence of light a more eroded but organized structure is observed. Indeed wettability/capillarity test shows that light degrades the plasma treatment both at and inside the fabric structure. However, in absence of light, although aging is very slow at the fabric surface, a decrease in capillary uptake by the fabric is detected. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Reverse‐Selective Microporous Membrane for Gas Separation
Authors: Sawamura Ken‐ichi , Izumi Teruaki , Kawasaki Kiyotoshi , Daikohara Shintaro , Ohsuna Tetsu , Takada Mitsuko , Sekine Yasushi , Kikuchi Eiichi , Matsukata Masahiko
Published: June 2009

Sort the bigs from the smalls: Reverse‐selective membranes, through which bigger molecules selectively permeate, are attractive for developing chemical processes. A new adsorption‐based reverse‐selective membrane that utilizes a Na cation occluded in a zeolitic framework is presented. The membrane developed enables the selective permeation and separation of bigger polar molecules, such as methanol and water, from hydrogen above 473 K.

magnified image

Reverse‐selective membranes, through which bigger molecules selectively permeate, are attractive for developing chemical processes utilizing hydrogen because they can maintain the high partial pressure of hydrogen required for their further downstream utilization. Although several of these chemical processes are operated above 473 K, membranes with outstanding reverse‐selective separation performance at these temperatures are still to be reported. Herein, we propose a new adsorption‐based reverse‐selective membrane that utilizes a Na cation occluded in a zeolitic framework. The membrane developed in this work, a compact Na+‐exchanged ZSM‐5 (NaZSM‐5) type zeolite membrane, enables us to selectively permeate and separate bigger polar molecules, such as methanol and water, from a stream containing hydrogen, above 473 K. On the other hand, a Na+‐free, H+‐exchanged ZSM‐5 (HZSM‐5) type zeolite membrane did not show separation properties at these temperatures. The microporous zeolite membrane developed in this study can be applied to a variety of chemical reaction systems to minimize energy consumption.
Bauphysikalische, ökologische und ökonomische Bewertung von geförderten Sanierungskonzepten in Wien
Authors: Korjenic Azra , Bitzinger Friedrich , Mahdavi Ardeshir
Published: June 2009

In diesem Beitrag wird die Nachhaltigkeit von Gebäudesanierungen untersucht, wobei die Reduzierung des Energieverbrauchs das oberste Ziel ist, was mit bis zu 80 % erreicht werden kann. Während in anderen Großstädten Europas das Konzept der Flächensanierung praktiziert wurde und wird, wird in Wien die “sanfte Sanierung” propagiert und auch gefördert. Die Stadt Wien hat dafür verschiedene Sanierungskonzepte bei der Hand. In dieser Untersuchung werden die verschiedenen geförderten Sanierungskonzepte anhand eines realen Beispiels gezeigt und rechnerisch überprüft. Ein Vergleich der verschiedenen Konzepte beleuchtet die einzelnen Punkte der Sanierung: Energieeffizienz, Sanierungskosten, Belastung für den Eigentümer bzw. Mieter der Wohnungen und Belastung für den Fördergeber (Land Wien). Die Ergebnisse ausgeführter Sanierungskonzepte brachten folgende Erkenntnisse bzw. Problemstellungen:

– die Sanierungsmaßnahmen kommen hauptsächlich den Mietern zugute, während der Kostenträger (Eigentümer) nur die Wertsteigerung als Nutzen hat;

– mangelnde Bereitschaft der Bewohner zur Sanierung;

– erhebliche Mehrkosten für Passivhaustechnik;

– zu geringe höchstzulässige Gesamtsanierungskosten.

Evaluation of retrofitting concepts and municipal sponsoring in Vienna.

Major energy efficiency improvements can be achieved via building stock retrofit. While in some major cities in Europe, mostly large‐area building retrofit measures have been targeted; in Vienna a gradual thermal improvement of the building stock has been practiced. Thereby, a number of different instruments and programs have been promoted by the regional government. In the present contribution, a number of such programs are compared and evaluated based on the demonstrative case of a concrete example. Thereby, multiple related issues were addressed: energy efficiency, retrofit expenses, burden for the building owners and tenants, and burden for the funding agency (Municipal of Vienna). The results suggest:

– the main beneficiary of retrofit programs are typically the tenants. The landlords benefit indirectly due to the appreciation of property value;

– there is a certain lack of willingness on the side of the occupants toward thermal building retrofit measures;

– achieving passive house standard in the course of retrofit measures cause significant additional costs;

– permissible (fundable) maximum total retrofit expenses has been set too low.
Combinatorial Strategies by Marine Cyanobacteria: Symplostatin 4, an Antimitotic Natural Dolastatin 10/15 Hybrid that Synergizes with the Coproduced HDAC Inhibitor Largazole
Authors: Taori Kanchan , Liu Yanxia , Paul Valerie J. , Luesch Hendrik
Published: June 2009

Combinatorial biosynthesis meets combinatorial pharmacology, cyanobacterial style: A new antimitotic natural product with features of both dolastatins 10 and 15 was isolated from the same Floridian Symploca sp. sample that produced the histone deacetylase inhibitor largazole. Both agents in combination are more effective in inhibiting cancer cell proliferation than either agent alone.

magnified image
Handbook of RNA Biochemistry: Student Edition. Edited by Roland Karl Hartmann and Albrecht Bindereif, Astrid Schön and Eric Westhof.
Authors: Corey David
Published: June 2009

Wiley‐VCH, Weinheim 2009, XLIII+931 pp., softcover € 99.00.—ISBN 978‐3‐527‐32534‐4

magnified image
Essentials of Chemical Biology: Structure and Dynamics of Biological Macromolecules. By Andrew D. Miller and Julian Tanner.
Authors: Deiters Alexander
Published: June 2009

Wiley, Hoboken 2008, 590 pp., softcover $ 75.00.—ISBN 978‐0‐470‐84531‐8

magnified image
Wiley Encyclopedia of Chemical Biology, Vols. 1–4. By Tadhg P. Begley.
Authors: Reymond Jean‐Louis
Published: June 2009

Wiley, Hoboken 2009, 3188 pp., hardcover $ 1200.00.—ISBN 978‐0‐471‐75477‐0

magnified image
Cover Picture: Proteolysis of Peptide Dendrimers (ChemBioChem 9/2009)
Authors: Sommer Peter , Fluxa Viviana S. , Darbre Tamis , Reymond Jean‐Louis
Published: June 2009

The cover picture shows the discovery of proteolysis sites within peptide dendrimers. On p. 1527 ff. of this issue, J.‐L. Reymond et al. explain how proteolytic cleavage within the branches of these molecular trees was found to be possible by proteases such as trypsin (Trp) or chymotrypsin (Chy) when the correct amino acid (Arg for Trp, Phe for Chy) was placed at the cleavage site. Protease‐reactive dendrimers were identified by screening a one‐bead–one‐compound combinatorial library of dendrimers (top left) using an on‐bead proteolysis assay (red indicates the presence of free amino termini after proteolysis). It was also possible to hide proteolysis sites from the proteases by using a higher degree of branching in the dendrimers (not shown). A space‐filling rendering of a peptide dendrimer and its cleavage products upon trypsin cleavage is shown. Cover design and realization by Louise A. Reymond and Viviana S. Fluxa.

magnified image
Randomized evaluation of two drug‐eluting stents with identical metallic platform and biodegradable polymer but different agents (paclitaxel or sirolimus) compared against bare stents: 1‐Year results of the PAINT trial
Authors: Lemos Pedro A. , Moulin Bruno , Perin Marco A. , Oliveira Ludmilla A.R.R. , Arruda J. Airton , Lima Valter C. , Lima Antonio A.G. , Caramori Paulo R.A. , Medeiros Cesar R. , Barbosa Mauricio R. , Brito Fabio S. , Ribeiro Expedito E. , Martinez Eulógio E.
Published: June 2009

Objectives: We tested two novel drug‐eluting stents (DES), covered with a biodegradable‐polymer carrier and releasing paclitaxel or sirolimus, which were compared against a bare metal stent (primary objective). The DES differed by the drug, but were identical otherwise, allowing to compare the anti‐restenosis effects of sirolimus versus paclitaxel (secondary objective). Background: The efficacy of novel DES with biodegradable polymers should be tested in the context of randomized trials, even when using drugs known to be effective, such as sirolimus and paclitaxel. Methods: Overall, 274 patients with de novo coronary lesions in native vessels scheduled for stent implantation were randomly assigned (2:2:1 ratio) for the paclitaxel (n = 111), sirolimus (n = 106), or bare metal stent (n = 57) groups. Angiographic follow‐up was obtained at 9 months and major cardiac adverse events up to 12 months. Results: Both paclitaxel and sirolimus stents reduced the 9‐month in‐stent late loss (0.54–0.44 mm, 0.32–0.43 mm, vs. 0.90–0.45 mm respectively), and 1‐year risk of target vessel revascularization and combined major adverse cardiac events (P < 0.05 for both, in all comparisons), compared with controls. Sirolimus stents had lower late loss than paclitaxel stents (P < 0.01), but similar 1‐year clinical outcomes. There were no differences in the risk of death, infarction, or stent thrombosis among the study groups. Conclusion: Both novel DES were effective in reducing neointimal hyperplasia and 1‐year re‐intervention, compared to bare metal stents. Our findings also suggest that sirolimus is more effective than paclitaxel in reducing angiographic neointima, although this effect was not associated with better clinical outcomes.© 2009 Wiley‐Liss, Inc.
Characteristics of adult patients with atrial septal defects presenting with paradoxical embolism
Authors: Bannan Amr , Shen Rhuna , Silvestry Frank E. , Herrmann Howard C.
Published: June 2009

Background: The association between patent foramen ovale (PFO), atrial septal aneurysm, and cryptogenic stroke due to paradoxical embolism has been established. The correlation between atrial septal defect (ASD) in adults and paradoxical embolism is less well defined. Methods: We examined our single center experience with 329 adult patients undergoing percutaneous device closure of interatrial communication defects to identify clinical and morphologic differences among adult patients with ASDs who presented with or without paradoxical embolism. Comparison was made with patients with PFO. Results: Although a significant left‐to‐right shunt was the predominant indication for ASD closure, 20 patients (14%) presented with a paradoxical embolism. These patients tended to be younger and had smaller defects (both by size and shunt ratio) than ASD patients without paradoxical embolism, and were more likely to be female than PFO patients. Conclusions: The incidence of adult patients with ASD who presented with paradoxical embolism is higher than expected and suggests that this diagnosis should be considered in patients with cryptogenic stroke. © 2009 Wiley‐Liss, Inc.
New onset atrial fibrillation after patent foramen ovale closure
Authors: Staubach Stephan , Steinberg Daniel H. , Zimmermann Wibke , Wawra Nikolaus , Wilson Neil , Wunderlich Nina , Sievert Horst
Published: June 2009

Objectives: In this study, we evaluated the incidence of new onset atrial fibrillation (symptomatic or detected by routine ECG) after patent foramen ovale (PFO‐) closure. Background: Although atrial fibrillation is known to occur in some patients following patent foramen ovale closure, the incidence and the risk associated with each device is not well known. Methods: We evaluated 1,349 consecutive patients who underwent PFO closure with an approved device and examined the incidence and risk factors associated with the development of atrial fibrillation. The patients had a mean age of 50 years and underwent PFO closure for cerebrovascular accident in 696 (51.6%), transient ischemic attack in 610 (45.2%), paradoxical embolism in 22 (1.6%), decompression sickness in 13 (0.9%), and other reasons including migraine headaches in 6 (0.4%) of cases. Results: Over a mean follow‐up period of 38.1 ± 28 months, 53 (3.9%) patients developed new onset atrial fibrillation, which is higher compared with an age‐matched population. Of these, 33 (62.3%) patients developed atrial fibrillation within 4 weeks and 8 (15%) within 6 months following PFO closure (totally 77% from 0 to 6 months). The event consisted of a single paroxysm lasting less than 48 hr in 23 patients, resolving either spontaneously or with cardioversion. 40 (75.5%) patients were symptomatic at the time of diagnosis. Thirty (56.6%) patients developed chronic atrial fibrillation. On multivariate analysis, advanced age and use of the STARFlex device predicted atrial fibrillation. Conclusions: The number of patients in whom atrial fibrillation was detected was relatively low. It is often a self‐limited complication of PFO closure that may occur more frequently in elderly patients and those treated with the STARFlex device. © 2009 Wiley‐Liss, Inc.
Fluoroscopy vs. Traditional guided femoral arterial access and the use of closure devices: A randomized controlled trial
Authors: Abu‐Fadel Mazen S. , Sparling Jeffrey M. , Zacharias Soni J. , Aston Christopher E. , Saucedo Jorge F. , Schechter Eliot , Hennebry Thomas A.
Published: June 2009

Objective: To compare the effectiveness of accessing the common femoral artery (CFA) using fluoroscopic guidance (FG) versus traditional anatomic landmark guidance (TALG) during cardiac catheterization and to determine the effect of the two modalities on the appropriateness for use of vascular closure devices (VCDs). Background: Previous studies have shown a consistent relationship between the head of the femur and the CFA, yet there is no prospective data validating the superiority of fluoroscopy‐assisted CFA access. Methods: A total of 972 patients were randomized to either FG or TALG access. The primary endpoint of the study was the angiographic suitability of the puncture site for VCD use. Secondary endpoints included arteriotomy location, time and number of attempts needed to obtain access, and the incidence of vascular complications. Results: Of these, 474 patients were randomized into the FG arm and 498 patients into the TALG arm. A total of 79.5% of patients in the fluoroscopy arm and 80.7% in the traditional arm (P = 0.7) were deemed angiographically suitable for VCD based on the arteriotomy. The fluoroscopy group had significantly less arteriotomies below the inferior border of the head of the femur (P = 0.03). Total time for sheath insertion (105.7 ± 130.7 vs. 106.5 ± 152.6 sec) and number of arterial punctures (1.1 ± 0.4 vs. 1.1 ± 0.5) did not differ among the FG and TALG, respectively. The rates of vascular complications were not different. Conclusion: The angiographic suitability for VCD was not different between FG and TALG groups. Fluoroscopy decreased the number of low arteriotomies. The time to sheath insertion, number of arterial punctures needed to obtain access, and the incidence of complications were also similar. © 2009 Wiley‐Liss, Inc.
Influence of Polyelectrolyte on DNA–RecA Nucleoprotein Filaments: Poly‐L‐Lysine Used as a Model
Authors: Guo Cunlan , Li Gaiping , Liu Zhelin , Sun Lanlan , Sun Yujing , Xu Fugang , Zhang Yue , Yang Tao , Li Zhuang
Published: June 2009

The effects of polyelectrolyte on the interaction of RecA protein and DNA are investigated in vitro by agarose gel electrophoresis and atomic force microscopy (see figure). Through changing the concentration, the length, and the addition orders of the polyelectrolyte, its effects on the DNA–RecA filaments are investigated and the probable mechanism is deduced.

magnified image

RecA of Escherichia coli and its active nucleoprotein filaments with DNA are important for the genomic integrity and the genetic diversity. The formation of the DNA‐RecA nucleoprotein filaments is a complex multiple‐step process and can be affected by many factors. In this work, the effects of poly‐L‐lysine (PLL) on the DNA‐RecA nucleoprotein filaments are investigated in vitro by agarose gel electrophoresis and atomic force microscopy (AFM). The observed morphologies vary with the concentration, the length, and the addition order of PLL. These distinctions provide information for the conformation change of DNA and the binding sites of RecA protein in the formation process of nucleoprotein filaments. Besides that, the comparison displays the effect of cationic polyelectrolyte on both inhibition and destabilization of the DNA‐RecA nucleoprotein filaments. The current study provides valuable insights for pharmacologic studies and gene delivery.
Electronic Studies on Oligothienylenevinylenes: Understanding the Nature of Their Ground and Excited Electronic States
Authors: Ponce Ortiz Rocío , González Sandra R. , Casado Juan , López Navarrete Juan T. , Officer David L. , Wagner Pawel , Earles John C. , Gordon Keith C.
Published: June 2009

The electronic and molecular structures of a family of oligothienylenevinylenes for organic solar cells are studied by means of UV/Vis, fluorescence and Raman spectroscopy, aided by quantum chemical calculations. By using different anchoring groups, the alteration of the electronic properties upon inserting electron‐withdrawing groups into different positions on the oligothienylenevinylene backbone is determined. In addition, a thorough study of the photophysical properties is carried out to understand their potential use in optoelectronic devices. The charge defect of one of these systems is analysed to elucidate the possible charge carriers photogenerated during device operation.
One‐Pot Fabrication of High‐Quality InP/ZnS (Core/Shell) Quantum Dots and Their Application to Cellular Imaging
Authors: Hussain Sahid , Won Nayoun , Nam Jutaek , Bang Jiwon , Chung Hyokyun , Kim Sungjee
Published: June 2009

True colors: High‐quality InP and InP/ZnS quantum dots (QDs) are obtained by means of a simple one‐pot method in the presence of polyethylene glycol (PEG). Rapid and size‐controlled reactions lead to highly crystalline and nearly monodisperse QDs at relatively low temperatures. The particles emit from cyan blue to far‐red, and are successfully used in cellular imaging (see figure).

magnified image
Non‐Random Distribution of Interleukin Receptors on the Cell Surface
Authors: Jenei Attila , Kormos József , Szentesi Gergely , Veres Adrienn J. , Varga Sándor , Bodnár Andrea , Damjanovich Sándor , Mátyus László
Published: June 2009

Spot the dots: Spatial organization of cell surface proteins plays a key role in the process of transmembrane signalling. Receptor clustering and changes in their cell surface distribution are often determining factors in the final outcome of ligand–receptor interactions. Herein, the authors show the applicability of Ripley's K(t) with additional algorithms a tool for analyzing the cell surface receptor patterns (see picture).

magnified image

Spatial organization of cell surface proteins plays a key role in the process of transmembrane signalling. Receptor clustering and changes in their cell surface distribution are often determining factors in the final outcome of ligand–receptor interactions. There are several techniques for assessing the distribution of protein molecules. Fluorescence resonance energy transfer (FRET) is an excellent tool for determining distance relationships of cell surface molecules. However, it does not provide information on the distribution of molecular clusters. Different kinds of microscopies fill this gap. The evaluation of the images provided by the listed techniques is often questionable. Herein we show the applicability of Ripley’s K(t) function as a tool for analyzing the cell surface receptor patterns (Y. Nakamura, et al., Nature 1994, 369, 330–333). We have implemented an effective image processing algorithm for fast localization of gold labels on biological samples. We investigated spatial organization of Interleukin‐2Rα and ‐15Rα (IL‐2Rα and IL‐15Rα) on a human CD4+leukaemia T‐cell line, Kit225 FT7.10 by using transmission electron microscopy (TEM). TEM analysis showed co‐clustering of the two types of α‐chains even on the few‐hundred‐nanometer scale. The analysis of our data may contribute to our understanding the action of the IL‐2/IL‐15 receptor system in T‐cell function.
Synthesis of labeled BCX‐4208, a potent inhibitor of purine nucleoside phosphorylase
Authors: Kamath Vivekanand P. , Juarez‐Brambila Jesus J. , Morris Philip E.
Published: June 2009

BCX‐4208, a novel inhibitor of the enzyme purine nucleoside phosphorylase, mimics the charged ribosyl oxocarbenium ion formed during the transition state of the enzyme‐catalyzed C‐N bond cleavage of nucleosides. A slow‐onset, tight‐binding inhibitor with a $\hbox{K}_{\rm i}^{*}$ of 16 ± 1.4 pM, BCX‐4208 is one of the most potent inhibitors known for the enzyme. In support of our BCX‐4208 clinical program, a mass spectrometric assay has been developed that required labeled BCX‐4208 as an internal standard. The synthesis of [2H]2‐BCX‐4208 and [13C]‐BCX‐4208 is described in this report. Copyright © 2009 John Wiley & Sons, Ltd.
Dysprosium‐sensitized chemiluminescence system for the determination of enoxacin in pharmaceutical preparations and biological fluids with flow‐injection sampling
Authors: Sun Han‐wen , Wu Yuan‐yuan , Li Li‐qing
Published: June 2009

A novel trivalence dysprosium(Dy3+)‐sensitized chemiluminescence method was developed for the first time for the determination of enoxacin (ENX) using flow‐injection sampling based on the chemiluminescence (CL) associated with the reaction of the Dy3+‐cerium(Ce(IV))‐S2O32−‐ENX system and the Dy3+‐MnO4− S2O32−‐ENX system. The analytical conditions for CL emission were investigated and optimized. The relationship between the CL intensity of ENX and its concentration has good linearity, with a correlation coefficient of 0.9984–0.9994. The limit of detection (LOD, 3σ) was 0.20 ng/mL for the Dy3+‐ENX‐S2O32−‐Ce(IV)‐H2SO4 system and 0.22 ng/mL for the Dy3+‐ENX‐S2O32−‐MnO4−‐HNO3 system. The relative standard deviation (RSD, n = 11) was 1.8% for 11 determinations of 60 ng/mL ENX. The proposed method was applied to the analysis of ENX in injections, serum and urine samples with a recovery of 98%–105%. A possible mechanism for this sensitized CL reaction is discussed by comparing the CL spectra with the fluorescence emission spectra. The proposed method represents a wide linear range, high sensitivity and accuracy, and can be used for the routine determination of ENX in pharmaceutical preparations and biological fluids. Copyright © 2009 John Wiley & Sons, Ltd.
LC‐MS: a powerful tool in workplace drug testing
Authors: Gallardo E. , Barroso M. , Queiroz J. A.
Published: June 2009

Workplace drug testing is a well‐established application of forensic toxicology and it aims to reduce workplace accidents caused by affected workers. Several classes of abused substances may be involved, such as alcohol, amphetamines, cannabis, cocaine, opiates and also prescription drugs, such as benzodiazepines.

The use of alternative biological specimens such as hair, oral fluid or sweat in workplace drug testing presents several advantages over urinalysis—mainly the fact that sample collection can be performed easily without infringing on the examinee's privacy, so the subject is more likely to perform the test. However, drugs are usually present in these alternative specimens at low concentrations and the amount of sample available for analysis is small. The use of highly sensitive techniques is therefore necessary.

In fact, the successful interface of liquid chromatography with mass spectrometry (LC‐MS) has brought a new light into bioanalytical and forensic sciences as it allows the detection of drugs and metabolites at concentrations that are difficult to analyse using the more commonly adopted GC‐MS based techniques.

This paper will discuss the importance of LC‐MS in supporting workplace drug‐testing programmes. The combination of LC‐MS with innovative instrumentation such as triple quadrupoles, ion traps and time‐of‐flight mass spectrometers will also be focused. Copyright © 2009 John Wiley & Sons, Ltd.
Counterfeiting in performance‐ and image‐enhancing drugs
Authors: Graham Michael R. , Ryan Paul , Baker Julien S. , Davies Bruce , Thomas Non‐Eleri , Cooper Stephen‐Mark. , Evans Peter , Easmon Sue , Walker Christopher J. , Cowan David , Kicman Andrew T.
Published: June 2009

The current drastic escalation in obesity may be contributing to the exponential rise in drugs used for image enhancement. Drugs such as anabolic‐androgenic steroids (AAS) are perceived as a viable method of achieving a perfect physique. They are also the most widely abused drugs in sport. The Internet has encouraged the abuse of expensive drugs, particularly human growth hormone (hGH), resulting in increased importation for personal use. The substantial increase in this market has opened up avenues for counterfeiting, estimated as a multi‐million pound business. The acute adverse effects from contaminated vials may result in a variety of pathologies including communicable diseases. In 2007, in the UK, a series of intramuscular abscesses, requiring surgical treatment, led us to study samples obtained from the underground market.

The analysis of 38 parenteral samples and 19 oral samples of tablets was performed by a World Anti‐Doping Agency (WADA) accredited laboratory, in an attempt to establish the extent of available counterfeit products. Fifty‐three per cent (20) of the injectable AAS esters and 21% (4) of the oral tablets were counterfeit. Culture and sensitivity revealed the presence of skin commensal organisms, which may have contributed to the development of the abscesses. Users of AAS and hGH for sport, including bodybuilding, are currently risking their health because of counterfeit and poorly controlled products. Copyright © 2009 John Wiley & Sons, Ltd.
Enhanced Electrogenerated Chemiluminescence of Tris(2,2′‐bipyridyl) Ruthenium(II)/tripropylamine in the Presence of Pyridine and Its Analogues
Authors: Jiang Ping , Yan Lei , Liu Yun‐Hua , Yuan Hong‐Yan , Xiao Dan
Published: June 2009

In the present work, we conducted an investigation on the electrochemical and ECL behavior of Ru(bpy)$\rm{ {_{3}^{2+}}}$/TPrA system in the presence of pyridine and its analogues on platinum and gold electrode. Results showed that pyridine and its analogues enhanced Ru(bpy)$\rm{ {_{3}^{2+}}}$/TPrA ECL signal and exhibited different enhancement effects on different electrodes. On platinum electrode, the maximum enhancement factor of about 5 was obtained. On gold electrode, a low‐oxidation‐potential (LOP) ECL signal occurred and increased.
Nanocomposite with Polypyrrole Encapsulated within SBA‐15 Mesoporous Silica: Preparation and Its Electrochemical Application
Authors: Dong Junping , Hu Yanyan , Xu Jiaqiang , Qu Xiaomin , Zhao Chongjun
Published: June 2009

The nanocomposite with polypyrrole (PPy) confined in ordered mesoporous silica SBA‐15 channels was synthesized by in situ electropolymerization. X‐ray diffraction, scanning electron microscopy, transmission electron microscopy, N2 adsorption/desorption, and FT‐IR studies indicated that the nanocomposite has the well‐ordered hexagonal structures and PPy was in situ polymerized into the channels instead of the outer surface of SBA‐15. Furthermore, the PPy/SBA‐15 nanocomposite was used as an electrode modifier. We found that the nanocomposite‐modified electrode exhibited good electrocatalytic activities for hydroquinone oxidation where PPy chains could facilitate the electron transfer between molecular sieves and electrode surface. Three dihydroxybenzene isomers (hydroquinone, catechol and resorcinol) have been successfully detected at PPy/SBA‐15 modified electrode by preconcentration of the analyte.
Electrochemiluminescence Sensor Based on Multiwalled Carbon Nanotubes Doped Polyvinyl Butyral Film Containing Ru(bpy)$\rm{ {_{3}^{2+}}}$ as Chemiluminescence Reagent
Authors: Yang Xia , Yuan Ruo , Chai Yaqin , Zhuo Ying , Mao Li , Liu Zhongyuan , Su Huilan , Yuan Shirong
Published: June 2009

An effective electrochemiluminescence (ECL) sensor was developed by combining Ru(bpy)$\rm{ {_{3}^{2+}}}$ with multiwalled carbon nanotubes(MWNTs) doped polyvinyl butyral (PVB) film. The doped film can prevent the leakage of Ru(bpy)$\rm{ {_{3}^{2+}}}$ efficiently and the immobilized Ru(bpy)$\rm{ {_{3}^{2+}}}$ kept its electrocatalytic activity toward the electrooxidation of tripropylamine (TPA), suggesting PVB and MWNTs were proper matrix to immobilize Ru(bpy)$\rm{ {_{3}^{2+}}}$ by hydrophobic interaction. Cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and electrochemiluminescent characterization were employed to study the presented sensor. A wide linear dynamic range of 6 orders of magnitude between ECL intensity and concentration of TPA was found from 1×10−8 M to 5×10−2 M, with a detection limit of 3.5×10−9 M.
Semi‐active tuned mass damper building systems: Design
Authors: Chey Min‐Ho , Chase J. Geoffrey , Mander John B. , Carr Athol J.
Published: June 2009

Passive and semi‐active tuned mass damper (PTMD and SATMD) building systems are proposed to mitigate structural response due to seismic loads. The structure's upper portion self plays a role either as a tuned mass passive damper or a semi‐active resetable device is adopted as a control feature for the PTMD, creating a SATMD system. Two‐degree‐of‐freedom analytical studies are employed to design the prototype structural system, specify its element characteristics and effectiveness for seismic responses, including defining the resetable device dynamics. The optimal parameters are derived for the large mass ratio by numerical analysis. For the SATMD building system the stiffness of the resetable device design is combined with rubber bearing stiffness. From parametric studies, effective practical control schemes can be derived for the SATMD system. To verify the principal efficacy of the conceptual system, the controlled system response is compared with the response spectrum of the earthquake suites used. The control ability of the SATMD scheme is compared with that of an uncontrolled (No TMD) and an ideal PTMD building systems for multi‐level seismic intensity. Copyright © 2009 John Wiley & Sons, Ltd.
Incidence and persistence of sleep complaints in a community older population
Authors: Fok Marcella , Stewart Robert , Besset Alain , Ritchie Karen , Prince Martin
Published: June 2009

Objectives

To investigate factors associated with incidence and persistence of sleep complaints in an older population, with particular focus on the role of depression, subclinical depression and physical health status as predictors.

Method

An analysis was carried out of data from the Gospel Oak Study: a community survey of 656 residents within a geographic catchment area in north London, aged 65 and over who were followed up after 1 year. Subjective sleep complaint was ascertained using a single question at baseline and follow‐up. Independent variables included age, sex, marital status, social class, number of physical illnesses, disability, social support deficit and depression (according to SHORT‐CARE: both a categorical measure and a scale based score).

Results

Baseline prevalence of sleep complaint was 44.7%. Incidence after 1 year was 21.4%, and persistence was 66.3%. After adjustment, female sex and depression predicted incidence of sleep complaint whereas only depression caseness predicted persistence of complaint. The population attributable fractions of depression caseness for incidence and persistence of sleep complaint were 37.4 and 23.4%, respectively. Positive but weaker associations were found between sub‐case depressive symptoms and these outcomes.

Conclusions

Depression was the strongest predictor of incidence and persistence of sleep complaints in this older sample. However, overall it accounted only for a minority of instances of incident/persistent symptoms. Copyright © 2009 John Wiley & Sons, Ltd.
Earlier stress exposure and subsequent major depression in aging women
Authors: Kasen Stephanie , Chen Henian , Sneed Joel R. , Cohen Patricia
Published: June 2009

Objective

Despite evidence that stress exposure earlier in the life course may have long‐term consequences for psychopathology, most models of vulnerability for late life depression are limited to current stressors or to retrospective reports of stress history. This study estimates the influences of earlier stressors assessed longitudinally on subsequent major depressive disorder (MDD) in women at average age 60 (range 50–75).

Method

MDD, negative life events (NLE), and marital stress were assessed multiple times in a community‐based sample of 565 women followed for three decades. Adverse events experienced in childhood also were assessed prior to outcome.

Results

Greater childhood adversity, earlier high levels of NLE and marital stress, and a more rapid increase in marital stress over time elevated the odds of MDD at average age 60 independent of all stressors and other salient risk factors. Childhood adversity was mediated in part by intervening risks. Prior depression, earlier poor health status, a more rapid deterioration in health with age, and current disability owing to physical problems also were related independently to later MDD.

Conclusions

These findings support the enduring effects of earlier stress burden on MDD in women into old age and, in light of the increasing proportion of older women in the population, have important clinical implications for identification and treatment of those at risk for depression. Findings also underscore the need to develop resources to counteract or buffer similar stress exposure in younger generations of women. Copyright © 2009 John Wiley & Sons, Ltd.
Plasma β‐amyloid and duration of Alzheimer's disease in adults with Down syndrome
Authors: Prasher V. P. , Sajith S. G. , Mehta P. , Zigman W. B. , Schupf N.
Published: June 2009

Objectives

To investigate the relation of plasma levels of Aβ peptides (Aβ1‐40 and Aβ1‐42) and apolipoprotein E (APOE) genotype to dementia status, and the duration of Alzheimer's disease (AD) in adults with Down syndrome (DS).

Methods

Adults with DS were recruited from community settings and followed up for a mean period of 6.7 years. Plasma levels Aβ1‐40 and Aβ1‐42 and APOE genotype were determined at the last visit.

Results

There were 83 nondemented participants and 44 participants with prevalent AD. Overall, plasma levels of Aβ1‐42, Aβ1‐40 and the ratio Aβ1‐42/Aβ1‐40 did not differ significantly between the adults with DS. Among demented participants, the mean level of Aβ1‐40 was significantly lower (157.0 vs. 195.3) and the ratio of Aβ1‐42/Aβ1‐40 was significantly higher (0.28 vs. 0.16) in those with more than 4 years duration of dementia than in those with 4 or fewer years' duration of dementia. This pattern was generally similar in those with and without an APOE ε4 allele.

Conclusions

There is an association between plasma Aβ peptide levels and the duration of AD in older persons with DS. The predictive and diagnostic roles of Aβ1‐42 and Aβ1‐40 measurements for AD, however, remain controversial. Change in Aβ peptide levels with onset of AD and with the duration of dementia may account for a lack of difference between prevalent cases and nondemented individuals and for variation in the predictive power of Aβ peptide levels. Copyright © 2009 John Wiley & Sons, Ltd.
Synthesis of carvacrol by Friedel–Crafts alkylation of o‐cresol with isopropanol using superacidic catalyst UDCaT‐5
Authors: Yadav Ganapati D. , Kamble Shashikant B.
Published: June 2009

BACKGROUND: Alkylation of o‐cresol with propylene or isopropyl alcohol (IPA) over solid acid catalysts results in the formation of carvacrol, which finds potential applications in the synthesis of fine chemicals, intermediates, specialty chemicals, flavours and fragrances.

RESULTS: The present work covers evaluation of novel mesoporous superacidic catalysts namely UDCaT‐4, UDCaT‐5 and UDCaT‐6 in the greener synthesis of carvacrol. The catalysts are modified versions of zirconia showing high catalytic activity, stability and reusability. The catalytic activity increases in the following order: UDCaT‐5 > UDCaT‐4 > UDCaT‐6 > sulfated zirconia. The process was optimized and a mathematical model developed to describe the reaction pathway in liquid phase. Carvacrol could be efficiently obtained with a selectivity up to 82% at an isopropanol conversion of 98% after 2 h over UDCaT‐5 at 180 °C.

CONCLUSION: The reaction is free from any external mass transfer as well as intraparticle diffusion limitations and is intrinsically kinetically controlled. An overall second‐order kinetic equation was used to fit the experimental data. The activation energy was found to be 19.2 kcal/mol. The reaction was carried out without any solvent in order to make the process cleaner and greener. Copyright © 2009 Society of Chemical Industry
A numbered day in the life
Authors: Kirkwood Ken
Published: June 2009

A story of Jim, a man who begins to habituate himself to hospital culture as that outsider known as the patient. Journal of Hospital Medicine 2009;4:326–327. © 2009 Society of Hospital Medicine
Thromboprophylaxis for hospitalized medical patients: A Multicenter Qualitative study
Authors: Cook Deborah , Tkaczyk Andrea , Lutz Kristina , McMullin Joseph , Brian Haynes R. , Douketis James
Published: June 2009

BACKGROUND:

Observational studies have documented that medical patients infrequently receive venous thromboembolism (VTE) prevention.

OBJECTIVE:

To understand the barriers to, and facilitators of, optimal thromboprophylaxis.

PATIENTS:

Hospitalized medical patients.

DESIGN:

We conducted in‐depth interviews with 15 nurses, 6 pharmacists, 12 physicians with both clinical and managerial experience, and 3 hospital administrators.

SETTING:

One university‐affiliated and 2 community hospitals.

INTERVENTION:

Interviews were audiotaped and transcribed verbatim. Transcripts were reviewed and interpreted independently in duplicate.

MEASUREMENT:

Analysis was conducted using grounded theory.

RESULTS:

Physicians and pharmacists affirmed that evidence supporting heparin is strong and understood. Clinicians, particularly nurses, reported that mobilization was important, but were uncertain about how much mobilization was enough. Participants believed that depending on individual physicians for VTE prevention is insufficient. The central finding was that multidisciplinary care was also perceived as a barrier to effective VTE prevention because it can lead to unclear accountability by role confusion. Participants believed that a comprehensive, systems approach was necessary. Suggestions included screening and risk‐stratifying all patients, preprinted orders at hospital admission that are regularly reevaluated, and audit and feedback programs. Patient or family‐mediated reminders, and administrative interventions, such as hiring more physiotherapists and profiling thromboprophylaxis in hospital accreditation, were also endorsed.

CONCLUSIONS:

Universal consideration of thromboprophylaxis finds common ground in multidisciplinary care. However, results of this qualitative study challenge the conviction that either individual physician efforts or multidisciplinary care are sufficient for optimal prevention. To ensure exemplary medical thromboprophylaxis, clinicians regarded coordinated, systemwide processes, aimed at patients, providers, and administrators as essential. Journal of Hospital Medicine 2009;4:269–275. © 2009 Society of Hospital Medicine.
Quantification of bedside teaching by an academic hospitalist group
Authors: Crumlish Colleen M. , Yialamas Maria A. , McMahon Graham T.
Published: June 2009

BACKGROUND:

Medical educators have raised serious concerns about the decline in bedside teaching and the effect of this decline on trainee skills. We investigated the fraction of time hospitalist attending physicians spend at the bedside during teaching rounds and how often physical examination skills are demonstrated.

METHODS:

In a prospective, observational study, the authors investigated the rounding behavior of members of Brigham and Women's Hospitalist Service. For 5 weeks from December 2007 to January 2008, interns and residents rotating on the hospitalist service reported in a daily e‐mail (1) total time spent with their attending during attending rounds, (2) time spent inside patient rooms during attending rounds, and (3) whether or not a physical examination finding or technique was demonstrated by their hospitalist attending.

RESULTS:

A total of 61 observations were reported (66% response). Hospitalists spent an average of 101 minutes on teaching rounds and an average of 17 minutes inside patient rooms or 17% of their teaching time at the bedside. Bedside teaching occurred during 61% of teaching sessions and physical examination teaching occurred during 38% of teaching sessions. Rounds that included time spent at the bedside were longer on average than rounds that did not include time spent at the bedside (122 vs. 69 minutes, P < 0.001).

CONCLUSIONS:

Bedside teaching makes up approximately 17% of the time that hospitalists at this medical center spend on teaching rounds. Physical examination teaching has become infrequent. Research to clarify optimal strategies to improve bedside teaching and its value in patient care is needed. Journal of Hospital Medicine 2009;4:304–307. © 2009 Society of Hospital Medicine.
Economic inequality in Nepal: Patterns and changes during the late 1990s and early 2000s
Authors: Wagle Udaya R.
Published: June 2009

Nepal has undergone enormous economic and political changes during the past two decades. Data suggest that these were accompanied by large and increasing economic inequality after the mid 1990s with income from house rental, employment, businesses and remittances as well as the stock of wealth in real estate and businesses constituting the leading sources. Considerable disparities existed by castes/ethnicities and spatial distinctions with upper caste Hindus and Newars and urban areas consolidating their command of resources. The deep‐seated socio‐cultural practices and changing political landscape appear to greatly affect the gulf between those with and without access to power. Copyright © 2009 John Wiley & Sons, Ltd.
Parkinsonism in Gaucher's disease type 1: Ten new cases and a review of the literature
Authors: Kraoua Ichraf , Stirnemann Jérôme , Ribeiro Maria João , Rouaud Tiphaine , Verin Marc , Annic Agnès , Rose Christian , Defebvre Luc , Réménieras Liliane , Schüpbach Michaël , Belmatoug Nadia , Vidailhet Marie , Sedel Frédéric
Published: June 2009

Parkinsonism has been described in patients with Gaucher's disease (GD). We reviewed the 10 cases of patients with both parkinsonism and GD recorded in the French national GD registry, as well as 49 previously published cases. Relative to the general population, parkinsonism in GD patients (1) was more frequent, (2) occurred at an earlier age, (3) responded less well to levodopa, and (4) was more frequently associated with signs of cortical dysfunction. Enzyme replacement therapy (ERT) and substrate reduction therapy (SRT) were ineffective on GD‐associated parkinsonism, suggesting that parkinsonism itself is not an indication for ERT or SRT in this setting. © 2009 Movement Disorder Society