bluuebunny/crossref_metadata_2025_split huggingface dataset:
Surface‐enhanced Raman scattering for medical diagnostics and biological imaging
Authors: Vo‐Dinh Tuan , Yan Fei , Wabuyele Musundi B. 
Published: July 2005

AbstractWe present recent development and applications of a surface‐enhanced Raman scattering (SERS) technology for use in medical diagnostics and biological imaging. For medical diagnostics, we use Raman‐active dye‐labeled DNA gene probes and nanostructured metallic substrates as SERS‐active platforms. The surface‐enhanced Raman gene probes can be used to detect DNA biotargets (e.g. gene sequences, bacteria and viral DNA) via hybridization to DNA sequences complementary to these probes. The SERS gene probes eliminate the need for radioactive labels and have great potential to provide both sensitivity, selectivity and label multiplexing for DNA sequencing and clinical assays. We also describe a hyperspectral surface‐enhanced Raman imaging (HSERI) system that combines imaging capabilities with SERS detection to identify cellular components with high spatial and temporal resolution. The HSERI system's application to biological imaging is demonstrated using Raman dye‐labeled silver nanoparticles in cellular systems. Copyright © 2005 John Wiley & Sons, Ltd.
Surface‐enhanced resonance Raman scattering of rhodamine 6G on Pt nanoaggregates
Authors: Kim Nam Hoon , Kim Kwan 
Published: July 2005

AbstractPlatinum aggregates composed of ∼17 nm Pt nanoparticles were found recently to exhibit fairly strong surface‐enhanced Raman scattering (SERS) for adsorbed benzenethiol. In order to broaden its utility as a SERS substrate, the surface‐enhanced resonance Raman scattering (SERRS) effect of these Pt nanoaggregates on Si wafers was examined in this work using rhodamine 6G (R6G) as the probe molecule with 514.5, 568 and 632.8 nm excitation. The SERRS excitation profile appeared to be closely related to the molecular absorption of R6G, implying that the surface enhancement itself would not influence significantly the wavelength dependence of the Raman intensity of R6G on Pt nanoaggregates. The surface roughness was found nonetheless to affect in an obvious manner the enhancement factor (EF) of R6G, eventually showing a levelling off behaviour of SERR intensity with increasing surface roughness. By comparing this with the SERS of benzenethiol, the EF for R6G with 514.5 nm excitation was estimated to be 5 × 104. Copyright © 2005 John Wiley & Sons, Ltd.
Adaptive silver films for surface‐enhanced Raman spectroscopy of biomolecules
Authors: Drachev Vladimir P. , Thoreson Mark D. , Nashine Vishal , Khaliullin Eldar N. , Ben‐Amotz Dor , Davisson V. Jo , Shalaev Vladimir M. 
Published: July 2005

AbstractThe interaction of biological molecules with a typical substrate for surface‐enhanced Raman scattering (SERS) often leads to their structural and functional changes. In this paper we describe SERS substrates, called adaptive silver films (ASFs), in which the biomaterial and the substrate act in concert to produce excellent Raman enhancement through local restructuring of the metal surface while at the same time preserving the properties (such as conformational state and binding activity) of the analyte. These adaptive substrates show great promise for SERS spectroscopy of many different types of biomolecules, and we provide several current examples of their use. Copyright © 2005 John Wiley & Sons, Ltd.
Surface‐enhanced Raman sensors: early history and the development of sensors for quantitative biowarfare agent and glucose detection
Authors: Haynes Christy L. , Yonzon Chanda Ranjit , Zhang Xiaoyu , Van Duyne Richard P. 
Published: July 2005

AbstractSurface‐enhanced Raman spectroscopy (SERS) is a powerful technique for the sensitive and selective detection of low‐concentration analytes. This paper includes a discussion of the early history of SERS, the concepts that must be appreciated to optimize the intensity of SERS and the development of SERS‐based sensors. In order to achieve the lowest limits of detection, both the relationship between surface nanostructure and laser excitation wavelength, as well as the analyte/surface binding chemistry, must be carefully optimized. This work exploits the highly tunable nature of nanoparticle optical properties to establish the first set of optimization conditions. The SERS enhancement factor, EFSERS, is optimized when the energy of the localized surface plasmon resonance (LSPR) lies between the energy of the excitation wavelength and the energy of the vibrational band of interest. With the narrow LSPRs used in this work, it is straightforward to achieve EFSERS ∼ 108. These optimization conditions were exploited to develop SERS‐based sensors for two important target molecules: a Bacillus anthracis biomarker and glucose in a serum protein mixture. Using these optimized film‐over‐nanosphere surfaces, an inexpensive, portable Raman spectrometer was used successfully to detect the infectious dose of Bacillus subtilis spores with only a 5‐s data collection. The biomarker used to detect the Bacillus subtilis spores binds irreversibly to SERS substrates, whereas other important biomolecules, such as glucose, do not have any measurable binding affinity to a bare silver surface. To overcome this difficulty, a biocompatible partition layer was self‐assembled on the SERS substrate before exposure to the analyte solution. Using the partition layer approach to concentrate glucose near the SERS‐active substrate, physiological glucose concentrations can be detected even in the presence of interfering serum proteins. Copyright © 2005 John Wiley & Sons, Ltd.
Surface‐enhanced Raman spectroscopy: advancements and applications
Authors: Tian Z. Q. 
Published: July 2005

AbstractSince the mid‐1990s, surface‐enhanced Raman scattering (SERS) has advanced greatly and gained wider application and a renewal of interest. There have been several new and creative developments, e.g. SERS of single molecules, nanostructures and transition metals, tip‐enhanced Raman scattering (TERS), surface‐enhanced hyper‐Raman scattering (SEHRS), ultraviolet‐excited SERS (UV‐SERS) and surface‐enhanced resonance Raman scattering (SERRS), and their wide applications in biology, medicine, materials science and electrochemistry. It is timely to publish a special issue reporting these initiatives and the progress made in the past 7 years. This issue consists of 30 invited articles that are roughly divided into three SERS research themes: theories, methods and applications. These up‐to‐date representatives of the research results clearly show that SERS is important not only for Raman spectroscopy and surface science but also for nanoscience. Copyright © 2005 John Wiley & Sons, Ltd.
Synthesis of Polyacrylonitrile‐block‐Polystyrene Copolymers by Atom Transfer Radical Polymerization
Authors: Lazzari Massimo , Chiantore Oscar , Mendichi Raniero , López‐Quintela M. Arturo 
Published: July 2005

AbstractSummary: The synthesis of polyacrylonitrile‐block‐polystyrene (PAN‐b‐PS) copolymers by atom transfer radical polymerization (ATRP) is reported. Chain extension of bromine terminated PAN macroinitiators with styrene was performed using a CuBr/N,N,N′,N″,N″‐pentamethyldiethylenetriamine catalyst system and 2‐cyanopyridine as a solvent. The first‐order kinetic plots of styrene consumption showed a significant curvature, indicating a progressive decrease in the concentration of active species during copolymerization. The loss of the bromide end group was mainly ascribed to the elimination of HBr, as shown by 1H NMR spectroscopy. By varying the molar ratio of either the catalyst or the monomer to the initiator, a series of PAN‐b‐PS copolymers were prepared, with polydispersities as low as 1.3, and molar compositions ranging from 8.6/91.4 to 35.5/64.5.1H NMR spectra of PAN‐b‐PS in DMF‐d7 at 80 °C.magnified image1H NMR spectra of PAN‐b‐PS in DMF‐d7 at 80 °C.
Unitary couplings, scattering suboperators and regular factorizations of bounded operator valued functions II
Authors: Boiko S. S. , Dubovoy V. K. 
Published: July 2005

AbstractIn the paper bilateral shifts are studied which generate factorizations of unitary couplings (in the system theory they play the part of channels). Subspaces of L2(𝔎), reducing the multiplication operator by eit, are investigated in the channel language. New criteria for regular divisibility of contractive operator functions in the class L∞ are obtained. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Polyelectrolyte Multilayer Microspheres as Carriers for Bienzyme System: Preparation and Characterization
Authors: Balabushevich Nadezda G. , Sukhorukov Gleb B. , Larionova Natalia I. 
Published: July 2005

AbstractSummary: Polyelectrolyte multilayer microspheres were prepared by alternating adsorption of dextran sulfate and protamine on melamine formaldehyde cores followed by the partial decomposition of the core. Peroxidase and glucose oxidase were immobilized in the prepared microspheres. Retention of enzymatic activity of the peroxidase/glucose oxidase system incorporated into the microspheres was demonstrated. Applicability of the bienzyme system immobilized in the microspheres for kinetic glucose assay was shown.SEM image of the polyelectrolyte multilayer microsphere.magnified imageSEM image of the polyelectrolyte multilayer microsphere.
Phase Transition Behaviors of Self‐Oscillating Polymer and Nano‐Gel Particles
Authors: Sakai Takamasa , Hara Yusuke , Yoshida Ryo 
Published: July 2005

AbstractSummary: Self‐oscillating polymers and nano‐gel particles consisting of N‐isopropylacrylamide and the ruthenium catalyst of the Belousov‐Zhabotinsky reaction have been prepared. In order to clarify the crosslinking effect on the self‐oscillating behavior, the phase transition behaviors were investigated by measuring the transmittance and the fluorescence intensity of the polymer solution and the gel bead suspension. Cooperative effects due to crosslinking will play an important role for the design of nanoactuators.Chemical structure of poly(NIPAAm‐co‐Ru(bpy)3).magnified imageChemical structure of poly(NIPAAm‐co‐Ru(bpy)3).
Base‐induced 1,4‐elimination:Insights from theory and mass spectrometry*
Authors: Bickelhaupt F. Matthias 
Published: July 2005

Abstract

I.
Introduction
347

II.
Gas‐Phase Ion–Molecule Reactions
348

III.
Scope and Applications of Gas‐Phase Base‐Induced 1,4‐Elimination
349

A.  Anionic and Cationic 1,4‐Elimination
349

B.  Anionic 1,4‐Elimination in an FT‐ICR Cell
350

C.  Anionic 1,4‐Elimination in an FA Flow Tube
351

IV.
Stereochemistry of 1,4‐Elimination
352

A.  Syn Versus Anti Stereochemistry
352

B.  Effect of E Versus Z Stereochemistry of the Substrate
353

V.
Mechanism of 1,4‐Elimination: E1cb Versus E2
353

A.  Base‐Induced 1,4‐Elimination of 1‐Alkoxy‐2‐Butenes
353

B.  Base‐Induced 1,4‐Elimination of 3‐Alkoxycyclohexenes
354

C.  New DFT Computations on Base‐Induced 1,4‐Eliminations
354

VI.
Conclusions and Outlook
358

Acknowledgment
359

References
359

Experimental and theoretical studies on gas‐phase base‐induced 1,4‐elimination reactions are summarized and discussed. The emphasis is on the synergy that is achieved by combining the complementary data from mass spectrometry and theoretical chemistry. The scope and applications of 1,4‐eliminations are discussed and compared with other elementary reactions; e.g., 1,2‐elimination and aliphatic (SN2) and allylic (SN2′) nucleophilic substitution. Furthermore, the syn versus anti stereochemistry of 1,4‐elimination reactions and the effect of E versus Z stereochemistry of the substrate are examined. Particular attention is paid to the mechanistic nature of 1,4‐elimination, i.e., E2 or E1cb, as well as special features such as the single‐well E2 and E1cb mechanism. Also, new results from density functional theory computations (BP86/TZ2P) are presented. © 2002 Wiley Periodicals, Inc., Mass Spec Rev 20:347–361, 2001; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mas.10007
Electrophysiological diagnostic criteria of Lambert–Eaton myasthenic syndrome
Authors: Oh Shin J. , Kurokawa Katsumi , Claussen Gwen C. , Ryan Hewitt F. 
Published: July 2005

AbstractVarious parameters of the repetitive nerve stimulation (RNS) test of the abductor digiti quinti muscle were analyzed statistically in 34 patients with Lambert–Eaton myasthenic syndrome (LEMS). The sensitivity and specificity of the increments after exercise and after 50‐HZ stimulation for the diagnosis of LEMS were compared with reference values in 40 normal subjects and data from 538 tests in patients with myasthenia gravis (MG). When we used a 100% increment (the “gold standard”) as the normal limit for the postexercise facilitation (PEF) or the high‐rate stimulation (HRS) test, the diagnosis of LEMS was confirmed in 29 (85%) cases. When a 60% increment was used as the normal limit, the diagnosis of LEMS was made in 97% of cases. In MG, a 60% increment was observed in only 4 of 538 cases by HRS and in none by the exercise test. Thus, the use of a 60% increment showed a sensitivity of 97% for the diagnosis of LEMS and a specificity of 99% in excluding MG. A 60% increment in either the PEF or HRS test for the diagnosis of LEMS is a desirable alternative to the 100% increment previously considered to be the gold standard for this diagnosis. Muscle Nerve, 2005
Noninvasive monitoring of muscle damage during reloading following limb disuse
Authors: Frimel Tiffany N. , Walter Glenn A. , Gibbs John D. , Gaidosh Gabriel S. , Vandenborne Krista 
Published: July 2005

AbstractCast immobilization causes skeletal muscle disuse atrophy and an increased susceptibility to muscle damage. The objective of this study was to explore the utility of noninvasive magnetic resonance (MR) imaging to monitor muscle damage in the lower hindlimb muscles of the mouse during reloading following cast immobilization and to compare the findings in different muscles. The hindlimbs of C57BL6 mice were immobilized for 2 weeks in plantarflexion using a bilateral casting model. Following immobilization the mice were allowed to reambulate and muscle damage was monitored at different times. Cage‐restricted reloading following cast immobilization induced a significant shift (P < 0.0001) in the transverse (T2) relaxation characteristics of the postural slow‐twitch soleus muscle, but not in the neighboring gastrocnemius. Soleus T2 values peaked at 2 days of reloading. Muscle‐specific changes in MR T2 relaxation properties correlated with uptake of Evans blue dye, a histological marker of muscle damage. This study demonstrates that T2 MR imaging can be implemented to monitor noninvasively and sequentially muscle‐specific damage during reloading following limb disuse. Muscle Nerve, 2005
Particle‐In‐Cell/Monte‐Carlo Simulation of Plasma and Neutral Gas Flow for the Inner Coating of PET Bottles by Plasma‐Based Ion Implantation. N2 Gas Plasma
Authors: Miyagawa Yoshiko , Tanaka Masaaki , Nakadate Hiroshi , Ikeyama Masami , Miyagawa Soji 
Published: July 2005

AbstractSummary: Plasma behavior inside of a PET bottle together with the gas flow has been analyzed under plasma‐based ion implantation (PBII) conditions. The software “PEGASUS” with the cylindrical coordinate system was used for the simulation. PEGASUS uses the particle‐in‐cell (PIC) method for the movement of charged particles in the electromagnetic field and the Monte Carlo method for collisions of ions, electrons, and neutrals in the plasma in a low‐pressure gas. The gas flow is analyzed by the Monte Carlo method. It gives spatial distributions of densities, velocities, fluxes, temperatures and pressures of each neutral species. The plasma simulation was coupled with the gas flow simulation, and the plasma behavior in the flowing N2 gas was analyzed. The gas pressure was 10 and 50 Pa; a positive pulse voltage (maximum voltage = 500 V) was applied to the center rod from where the gas flows. Time evolutions of spatial distributions of the potential and the densities of ions, electrons and radicals in the coating system were obtained together with the flux of ions and electrons on the target surface.Time evolution of spatial distribution of N ion density. Conditions: N2 gas: 10 Pa, Vmax = 500 V, γ = 1.magnified imageTime evolution of spatial distribution of N ion density. Conditions: N2 gas: 10 Pa, Vmax = 500 V, γ = 1.
Crystal structure and magnetic properties of mixed compounds Nd1–xRxCo3 (R = Gd, Tb)
Authors: Ouyang Z. W. , Rao G. H. , Liu W. F. , Liu G. Y. , Feng X. M. , Liang J. K. 
Published: July 2005

AbstractThe crystal structure and magnetic properties of Nd1–xRxCo3 (R = Gd, Tb) have been investigated by means of X‐ray powder diffraction and magnetic measurements. Spin reorientation and magnetization compensation are observed in both systems. The saturation magnetization MS of Nd1–xTbxCo3 exhibits an anomaly at a critical concentration xc ≈ 0.55, whereas no such an anomaly is observed for Nd1–xGdxCo3. These observations could be understood by considering the difference of the anisotropy between Tb3+ and Gd3+ ions. The type of magnetocrystalline anisotropy of the compounds is derived based on X‐ray diffraction patterns of the field‐aligned samples. For Nd1–xTbxCo3, the anisotropy near xc is weak with an undefined easy magnetization direction. On the Nd‐rich side, the anisotropy exhibits a strong temperature dependence. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Use of the modified Ginzburg–Landau equations in high temperature superconductors
Authors: Shehata L. N. , Taha H. M. 
Published: July 2005

AbstractThe modified Ginzburg–Landau equations are used to study some selected problems for the high temperature superconductors. The derivations of modified Ginzburg–Landau equations are briefly demonstrated by taking into consideration the layered features of the sample according to the relation between the coherence length and the separation distance of the layers. The domain wall energy, the maximum supercurrent and the parallel critical field of high temperature superconducting thin film were evaluated. Comparison with previous works is given. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Low‐energy spectrum of one‐dimensional generalized Wigner lattice
Authors: Slavin V. 
Published: July 2005

AbstractThe low‐energy spectrum of one‐dimensional lattice electron system with long‐range inter‐electron repulsion is studied at arbitrary electron concentration, ρ. It is established that the value of the gap in this spectrum is an oscillating function of inverse electron concentration. This value tends to zero at ρ = 1/q (q = 1, 2 …), reaching the maximum at ρ = 2/(2q + 1). It is shown that the low‐energy spectrum of the system under consideration may be described in terms of one‐dimensional structures which are analogues of domains in one‐dimensional spin systems. The question about these “domains” decay is considered. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
First‐principles calculations of the CaF2 bulk and surface electronic structure
Authors: Shi H. , Eglitis R. I. , Borstel G. 
Published: July 2005

AbstractWe present and discuss the results of calculations of the CaF2 bulk and surface electronic structure. These are based on the ab initio Hartree–Fock (HF) method with electron correlation corrections and on Density Functional Theory (DFT) calculations with different exchange‐correlation functionals, including hybrid exchange techniques. Both approaches use the localised Gaussian‐type basis set. According to our calculations the ab initio HF method considerably overestimates (20.77 eV) the optical band gap, whereas the density functional calculations based on the Kohn–Sham equation with a number of exchange‐correlation functionals, including local density approximation (LDA) (8.72 eV), generalized gradient approximations (GGA) by Perdew and Wang (PW) (8.51 eV), and Perdew, Burke, and Ernzerhof (PBE) (8.45 eV) underestimate it. Our results show that the best agreement with experiment (12.1 eV) can be obtained using a hybrid HF–DFT exchange functional, in which Hartree–Fock exchange is mixed with DFT exchange functionals, using Beckes three parameter method, combined with the non‐local correlation functionals by Perdew and Wang (B3PW) (10.96 eV). We also present calculations of CaF2(111), (110), and (100) surfaces. Our calculated surface energies using the hybrid B3PW method confirm that the CaF2(111) surface is the most stable one, in agreement with the experiment. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Characterization of carbofuran photodegradation by‐products by liquid chromatography/hybrid quadrupole time‐of‐flight mass spectrometry
Authors: Detomaso Antonia , Mascolo Giuseppe , Lopez Antonio 
Published: July 2005

AbstractAn Erratum has been published for this article in Rapid Communications in Mass Spectrometry 19(17) 2005, 2480.
The structural elucidation of by‐products arising from carbofuran photodegradation using a high‐pressure UV lamp has been investigated by liquid chromatography/electrospray ionization tandem mass spectrometry (LC/ESI‐MS/MS) employing a quadrupole time‐of‐flight mass spectrometer. Exact mass measurements of the [M + H]+ ions of the by‐products and of product ions allowed the elemental formulae and related structures of seven photodegradation by‐products (resulting, respectively, from photo‐Fries rearrangement, hydroxylation of the benzene ring, oxidation of the 2,3‐dihydrobenzofuran ring, cleavage of the carbamate group, hydrolysis of the ether group and the newly observed radical coupling and decarboxylation processes) to be determined confidently. Accurate mass measurements of product ions allowed ambiguities to be removed concerning neutral losses having the same nominal mass, namely CO and C2H4, allowing the fragmentation patterns to be rationalized. Copyright © 2005 John Wiley & Sons, Ltd.
Quantitative analysis of the farnesyl transferase inhibitor lonafarnib (Sarasar™, SCH66336) in human plasma using high‐performance liquid chromatography coupled with tandem mass spectrometry
Authors: Appels Natalie M. G. M. , van Maanen Maria J. , Rosing Hilde , Schellens Jan H. M. , Beijnen Jos H. 
Published: July 2005

AbstractLonafarnib is a novel anticancer drug that inhibits farnesyl transferase. To assess its pharmacokinetic properties, we developed a sensitive and quantitative assay using liquid chromatography coupled with tandem mass spectrometry for the determination of lonafarnib levels in human plasma. Sample pretreatment consisted of the addition of an isotopically labeled internal standard and protein precipitation with acetonitrile using 100 µL plasma. Chromatographic separation was performed on an Inertsil ODS‐3 analytical column (50 × 2.1 mm i.d., particle size 5 µm) with acetonitrile/water/formic acid (50:50:0.05, v/v/v) as the mobile phase, at a flow rate of 0.2 mL/min. The analytical run time was 8 min. An API365 triple quadrupole mass spectrometer was used for specific and sensitive detection. It was operated in the positive ion mode and multiple reaction monitoring was used for drug quantification. The method was validated using a concentration range of 2.5 to 2500 ng/mL lonafarnib. Validation of the assay was performed according to the most recent FDA guidelines for bioanalytical method validation and all results were within the requirements. The described method was successfully applied to support a clinical phase I trial with lonafarnib. Copyright © 2005 John Wiley & Sons, Ltd.