bluuebunny/crossref_metadata_2025_split huggingface dataset:
Study of asymmetric wavenumber shift of the Fermi doublet ν1 − 2ν2 in the Raman spectrum of liquid carbon disulfide
Authors: Li Dong‐Fei , Jiang Xiu‐Lan , Cao Biao , Li Zuo‐Wei , Gao Shu‐Qin , Zhou Mi , Men Zhi‐Wei , Zhai Nai‐Cui 
Published: October 2009

AbstractThe Raman spectra of liquid carbon disulfide (CS2) diluted with benzene (C6H6) have been measured. By changing the CS2, the concentration, we found an asymmetric wavenumber shift phenomenon. With decreasing concentration of CS2, the position of the ν1 (655 cm−1) band remains practically unchanged, and the 2ν2 (796 cm−1) band shifts toward higher wavenumbers. To interpret this asymmetric wavenumber shift phenomenon of the Fermi doublet ν1 − 2ν2 in the Raman spectra satisfactorily, we propose a modified Bertran model. The values of the Fermi resonance (FR) parameters of CS2 at different concentrations were calculated using the Bertran equations. In addition, we found the fundamental ν2, which should be independent of the FR interaction, shifted to higher wavenumbers as the concentration decreased. This shift was probably driven by the tuning of the FR. Copyright © 2009 John Wiley & Sons, Ltd.
PCR experion automated electrophoresis system to detect Listeria monocytogenes in foods
Authors: Delibato Elisabetta , Gattuso Antonietta , Minucci Angelo , Auricchio Bruna , De Medici Dario , Toti Laura , Castagnola Massimo , Capoluongo Ettore , Gianfranceschi Monica Virginia 
Published: October 2009

AbstractListeria monocytogenes is frequently found as a contaminant in raw and ready‐to‐eat foods. The ability of L. monocytogenes to multiply at refrigeration temperatures and to grow in a wide range of pH values is of particular concern for food safety. According to the European Union regulation on microbiological criteria for foodstuffs, L. monocytogenes must be absent in some categories of ready‐to‐eat foods. The standard microbiological method for L. monocytogenes detection in foods (ISO 11290‐1: 1996 (ISO, International Organization for Standardization)) is cost and time consuming. Developments of rapid, cost‐effective and automated diagnostic methods to detect food‐borne pathogens in foods continue to be a major concern for the industry and public health. The aim of this study was the development of a rapid, sensitive and specific molecular detection method for L. monocytogenes. To this purpose, we have applied a capillary electrophoresis method to a PCR protocol (PCR‐EES (EES, experion automated electrophoresis system)) for detecting L. monocytogenes in food. In particular, a microfluidic chip‐based automated electrophoresis system (experion automated electrophoresis system, Bio‐Rad Laboratories, USA) was used for the rapid and automatic analysis of the amplicons. Fifty naturally contaminated samples were analysed with this method and the results were compared with those obtained with ISO method. Moreover, the microfluidic chip‐based automated electrophoresis system was compared with classical gel electrophoresis (PCR‐CGE). The results showed that after 24 h of culture enrichment, the PCR‐EES showed a relative accuracy of 100% with ISO, while using PCR‐CGE decreased it down to 96%. After 48 h of enrichment, both PCR‐EES and PCR‐CGE showed an accuracy of 100% with ISO.
Identifying PTSD personality subtypes in a workplace trauma sample
Authors: Sellbom Martin , Bagby R. Michael 
Published: October 2009

AbstractThe authors sought to identify personality clusters derived from the Minnesota Multiphasic Personality Inventory‐2 (MMPI‐2) Personality Psychopathology Five Scales in a sample of workplace claimants with posttraumatic stress disorder (PTSD). Three clusters—low pathology, internalizing, and externalizing were recovered similar to those obtained by M. W. Miller and colleagues (2003, 2004, 2007) in samples of combat veterans and sexual assault victims. Internalizers and externalizers scored comparably on measures of PTSD symptom severity, general distress, and negative affect. Internalizers were uniquely characterized by anhedonia and depressed mood; externalizers by antisocial behavior, substance abuse, and anger/aggression.
Monitoring interstitial m‐THPC‐PDT in vivo using fluorescence and reflectance spectroscopy
Authors: Kruijt Bastiaan , van der Ploeg‐van den Heuvel Angelique , de Bruijn Henriette S. , Sterenborg Henricus J.C.M. , Amelink Arjen , Robinson Dominic J. 
Published: October 2009

AbstractBackground and ObjectiveIn order to understand the mechanisms of photodynamic therapy (PDT) it is important to monitor parameters during illumination that yield information on deposited PDT dose. The aim of this study is to investigate the possibility of monitoring implicit parameters, such as photobleaching, in addition to monitoring explicit parameters (fluence (rate), oxygenation, photosensitizer concentration) directly or indirectly. These parameters are monitored during PDT without interrupting the therapeutic illumination.Materials and MethodsRats were injected with 0.3 mg kg−1 m‐THPC. Sixteen hours after administration the abdominal muscle in rats was irradiated for 1,500 seconds using clinically relevant fluence rates of 50, 100, and 250 mW cm−1 of diffuser length at 652 nm. In addition to the linear diffuser for delivering treatment light, isotropic fiber‐optic probes and fiber‐optic probes for differential path‐length spectroscopy (DPS) were placed on both sides of the muscle to monitor tissue physiological parameters, fluence rate, and fluorescence.ResultsThe m‐THPC treatment groups show a decrease in fluence rate throughout PDT of 16%, 19%, and 27% for the 50, 100, and 250 mW cm−1 groups, respectively. Both during and post‐PDT differences in vascular response between treatment groups and animals within the same treatment group are observed. Furthermore we show fluence rate dependent bleaching of m‐THPC up to a measured fluence rate of 100 mW cm−1.ConclusionThe data presented in this study show the possibility of simultaneously monitoring fluence (rate), fluorescence, hemoglobin oxygen saturation, and blood volume during PDT without interruptions to the therapeutic illumination. Differences in saturation profiles between animals and treatment groups indicate differences in vascular response during illumination. Furthermore, the relationship between fluence rate and m‐THPC fluorescence photobleaching is complex in an interstitial environment. Lasers Surg. Med. 41:653–664, 2009. © 2009 Wiley‐Liss, Inc.
Simulations of measured photobleaching kinetics in human basal cell carcinomas suggest blood flow reductions during ALA‐PDT
Authors: Wang Ken Kang‐Hsin , Cottrell William J. , Mitra Soumya , Oseroff Allan R. , Foster Thomas H. 
Published: October 2009

AbstractBackground and ObjectiveIn a recently completed pilot clinical study at Roswell Park Cancer Institute, patients with superficial basal cell carcinoma (sBCC) received topical application of 20% 5‐aminolevulinic acid (ALA) and were irradiated with 633 nm light at 10–150 mW cm−2. Protoporphyrin IX (PpIX) photobleaching in the lesion and the adjacent perilesion normal margin was monitored by fluorescence spectroscopy. In most cases, the rate of bleaching slowed as treatment progressed, leaving a fraction of the PpIX unbleached despite sustained irradiation. To account for this feature, we hypothesized a decrease in blood flow during ALA‐photodynamic therapy (PDT) that reduced the rate of oxygen transported to the tissue and therefore attenuated the photobleaching process. We have performed a detailed analysis of this hypothesis.Study Design/Materials and MethodsWe used a comprehensive, previously published mathematical model to simulate the effects of therapy‐induced blood flow reduction on the measured PpIX photobleaching. This mathematical model of PDT in vivo incorporates a singlet‐oxygen‐mediated photobleaching mechanism, dynamic unloading of oxygen from hemoglobin, and provides for blood flow velocity changes. It permits simulation of the in vivo photobleaching of PpIX in this patient population over the full range of irradiances and fluences.ResultsThe results suggest that the physiological equivalent of discrete blood flow reductions is necessary to simulate successfully the features of the bleaching data over the entire treatment fluence regime. Furthermore, the magnitude of the blood flow changes in the normal tissue margin and lesion for a wide range of irradiances is consistent with a nitric‐oxide‐mediated mechanism of vasoconstriction.ConclusionA detailed numerical study using a comprehensive PDT dosimetry model is consistent with the hypothesis that the observed trends in the in vivo PpIX photobleaching data from patients may be explained on the basis of therapy‐induced blood flow reductions at specific fluences. Lasers Surg. Med. 41:686–696, 2009. © 2009 Wiley‐Liss, Inc.
Novel wavelengths for laser nerve stimulation
Authors: McCaughey Ryan G. , Chlebicki Cara , Wong Brian J.F. 
Published: October 2009

AbstractBackgroundLaser light is known to stimulate nerves. This study investigated alternative wavelengths for nerve stimulation.Materials and MethodsThe sciatic nerves of rats were irradiated with four different lasers—a Ho:YAG (2100 nm), a Yb:glass fiber laser (1495 nm) and diode lasers (1450 nm and 1540 nm).ResultsAll lasers evoked a visible leg twitch response, and electromyography confirmed muscle activation. The Yb:glass laser at 1495 nm delivered through a single mode fiber was found to be the most effective stimulus. The stimulation threshold for a 2 millisecond pulse from the Yb:glass laser was determined to be 3.7±2.8 mJ/cm2.ConclusionsThe Yb:glass laser has the potential for use in neurostimulation, as an alternative to electrical stimulation. Lasers Surg. Med. 42:69–75, 2010. © 2009 Wiley‐Liss, Inc.
Electrochemical corrosion behavior of X80 pipeline steel in a near‐neutral pH solution
Authors: Xue H. B. , Cheng Y. F. 
Published: October 2009

AbstractIn this work, the electrochemical corrosion behavior of X80 pipeline steel was investigated in a near‐neutral pH solution using electrochemical impedance spectroscopy (EIC) and photo‐electrochemical (PEC) measurements as well as X‐ray photo‐electron spectroscopy (XPS) technique. The effects of hydrogen‐charging and stress were considered. The results show that the steel is in an active dissolution state, and a layer of corrosion product is formed and deposited on the electrode surface, which is subjected to further oxidation to form ferric oxide and hydroxide. Photo‐illumination enhances anodic dissolution of the steel when it is under anodic polarization due to destroying of the corrosion product film. When the steel is under cathodic polarization, the cathodic current density decreases upon laser illumination due to the photo‐oxidation of hydrogen atoms generated during cathodic reactions, which behaves as an anodic reaction to offset the cathodic current density. Hydrogen‐charging and stress decrease the corrosion resistance of the steel and enhance the dissolution rate of the steel.
Surface Relief Gratings in Azobenzene‐Containing Polymers with Linear and Star‐Branched Architectures: A Comparison
Authors: Gharagozloo‐Hubmann Kati , Kulikovska Olga , Börger Volker , Menzel Henning , Stumpe Joachim 
Published: October 2009

AbstractThe influence of molecular architecture on light‐induced SRG formation was investigated. Polymers with different degree of branching were synthesized by ATRP and functionalized with azobenzene chromophores. The polymers differ only in their architecture – linear, 4‐, 6‐, or 12‐arms stars. The photo‐induced dichroism as well as the efficiency of SRG formation was similar for all polymers of this series. New consideration for the origin of the driving force was used to explain this behavior. The comparable SRG inscription rate in differently branched polymers can be rationalized by assuming that azobenzene acts as an internal molecular motor and can cause a non‐turbulent motion on a scale smaller than that on which normal entanglement restriction forces act.magnified image
Steric Coordination Control of Interchain Interactions in Conducting Metallopolymers
Authors: He Susan , Dennis Ashlyn E. , Smith Rhett C. 
Published: October 2009

AbstractThe solution processability of a conducting metallopolymer (CMP1) based on a 2,2′‐bipyridyl (bipy) derivatized poly(p‐phenylene vinylene) (PPV) backbone has been accomplished by the strategic placement of sterically demanding mesityl side chains. The enhanced solubility of CMP1 can be traced to the prevention of coordinative crosslinking between polymer chains. The sterically enforced 1:1 bipy/metal ratio was confirmed by job analysis of absorption spectroscopic titration data. In addition to enhanced processability, this strategy also leads to twice as many metal ions, and consequently twice the charge, on CMP1 versus traditional bipyridyl‐PPV metallopolymers that are typified by a 2:1 bipy/metal ratio with certain metals.magnified image
Determination of metabolite profiles in tropical wines by 1H NMR spectroscopy and chemometrics
Authors: da Silva Neto Humberto G. , da Silva João B. P. , Pereira Giuliano E. , Hallwass Fernando 
Published: October 2009

AbstractTraditionally, wines are produced in temperate climate zones, with one harvest per year. Tropical wines are a new concept of vitiviniculture that is being developed, principally in Brazil. The new Brazilian frontier is located in the northeast region (São Francisco River Valley) in Pernambuco State, close to the equator, between 8 and 9°S. Compared with other Brazilian and worldwide vineyards, the grapes of this region possess peculiar characteristics. The aim of this work is a preliminary study of commercial São Francisco River Valley wines, analyzing their metabolite profiles by 1H NMR and chemometric methods. Copyright © 2009 John Wiley & Sons, Ltd.
1H and 13C NMR assignments of all three isomeric o‐fluoronaphthaldehydes and three o‐fluorophenanthrene aldehydes
Authors: Busacca Carl A. , Campbell Scot , Gonnella Nina C. , Senanayake Chris H. 
Published: October 2009

AbstractThree isomeric o‐fluoronaphthaldehydes, 9‐fluorophenanthrene, and three previously unreported o‐fluorophenanthrene aldehydes were analyzed in detail by multiple NMR techniques to provide unambiguous assignment of structures and resonances. The six aldehydes serve as the key starting materials for novel chiral ligands used in highly enantioselective rhodium‐catalyzed asymmetric hydrogenation reactions. Copyright © 2009 John Wiley & Sons, Ltd.
Reactivity of the disilyne RSiSiR (R = SiiPr[CH(SiMe3)2]2) toward bis(silylcyanide) forming a 1,4‐diaza‐2,3‐disilabenzene analog
Authors: Takeuchi Katsuhiko , Ichinohe Masaaki , Sekiguchi Akira , Guo Jing‐Dong , Nagase Shigeru 
Published: October 2009

AbstractThe reaction of 1,1,4,4‐tetrakis[bis(trimethylsilyl)methyl]‐1,4‐diisopropyl‐2‐tetrasilyne 1 with 1,3‐bis(cyanodimethylsilyl)propane 4 produced the 1:1 adduct, 1,4‐diaza‐2,3‐disilabenzene analog 5 as deep red crystals, which was characterized by spectroscopic data and X‐ray crystallography. Theoretical calculations on the reaction between the disilyne and silylcyanide show that the reaction proceeds via σ‐coordination of silylcyanide, in which two molecules of silylcyanide coordinate with the sp‐silicon atoms of disilyne, enabling CC bond formation. Copyright © 2009 John Wiley & Sons, Ltd.
Synthesis and characterization of thermoresponsive polymers containing reduction‐sensitive disulfide linkage
Authors: Li Lihua , Jiang Xulin , Zhuo Renxi 
Published: October 2009

AbstractA novel class of thermoresponsive and reduction‐sensitive polymer, p(PEG‐MEMA‐co‐Boc‐Cyst‐MMAm), containing disulfide linkages and removable hydrophobic tert‐butyloxycarbonyl side chains was synthesized. The cloud points (CP) of p(PEG‐MEMA‐co‐Boc‐Cyst‐MMAm) in water determined by UV/VIS spectrometer were between 20 °C and 57 °C, which shows that the CP can be tuned by adjusting the copolymer composition. Moreover, the thermosensitive polymers p(PEG‐MEMA‐co‐Boc‐Cyst‐MMAm) formed stable nanoparticles in neutral aqueous medium, but rapidly destabilized in an reductive environment mimicking the intracellular space making them suitable for cytoplasmic drug delivery. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5989–5997, 2009
Well‐defined amphiphilic graft copolymer consisting of hydrophilic poly(acrylic acid) backbone and hydrophobic poly(vinyl acetate) side chains
Authors: Li Yaogong , Zhang Yaqin , Yang Dong , Feng Chun , Zhai Sujuan , Hu Jianhua , Lu Guolin , Huang Xiaoyu 
Published: October 2009

AbstractA series of well‐defined amphiphilic graft copolymers containing hydrophilic poly(acrylic acid) (PAA) backbone and hydrophobic poly(vinyl acetate) (PVAc) side chains were synthesized via sequential reversible addition‐fragmentation chain transfer (RAFT) polymerization followed by selective hydrolysis of poly(tert‐butyl acrylate) backbone. A new Br‐containing acrylate monomer, tert‐butyl 2‐((2‐bromopropanoyloxy)methyl) acrylate, was first prepared, which can be polymerized via RAFT in a controlled way to obtain a well‐defined homopolymer with narrow molecular weight distribution (Mw/Mn = 1.08). This homopolymer was transformed into xanthate‐functionalized macromolecular chain transfer agent by reacting with o‐ethyl xanthic acid potassium salt. Grafting‐from strategy was employed to synthesize PtBA‐g‐PVAc well‐defined graft copolymers with narrow molecular weight distributions (Mw/Mn < 1.40) via RAFT of vinyl acetate using macromolecular chain transfer agent. The final PAA‐g‐PVAc amphiphilic graft copolymers were obtained by selective acidic hydrolysis of PtBA backbone in acidic environment without affecting the side chains. The critical micelle concentrations in aqueous media were determined by fluorescence probe technique. The micelle morphologies were found to be spheres. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 6032–6043, 2009
Synthesis and eutectic behavior of liquid crystalline copolyesters
Authors: Wang Xiuzhen , Bu Haishan , Luise Robert R. 
Published: October 2009

AbstractA series of liquid crystalline copolyesters, derived from 1,4‐hydroxy‐benzoic acid (HBA), 6‐hydroxy‐2‐naphthoic acid (HNA), terephthalic acid (TA), and hydroquinone (HQ), were prepared; crystallization, melting and solid‐state structure of the copolyesters were studied by using differential scanning calorimetry (DSC) and wide‐angle x‐ray diffraction (WAXD). It was found that the variation of melting point of the copolyesters with increasing HBA mol % exhibits eutectic melting behavior at a constant mole ratio of HNA, and the extrapolated eutectic temperature decreases linearly with increasing HNA mol %. WAXD analysis of the copolyesters indicates that the d‐spacing related to three‐dimensional order increases first and then decreases with increasing HBA mol %. The increase of the d‐spacing, consistent with looser packing of chains, leads to the reduction of melting point and most likely accounts for the eutectic behavior observed. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 2171–2177, 2009
Enhanced hydrogen bonding and its dramatic impact on deformation behaviors in a biomedical poly(carbonate urethane) with fluorinated chain extender
Authors: Na Bing , Lv Ruihua , Xu Wenfei , Tian Nana , Li Jiehua , Tan Hong , Fu Qiang 
Published: October 2009

AbstractThe enhanced hydrogen bonding, manifested by significant frequency decreasing of both NH and CO stretching vibrations, is confirmed in a biomedical poly(carbonate urethane) with fluorinated chain extender. It gives rise to preferential association among hard segments and thus promoted microphase separation, which is responsible for the plastic deformation behaviors of the fluorinated poly(carbonate urethane). Furthermore, the segmental orientation, including both soft and hard segments, has been well correlated with the enhanced hydrogen bonding as well as promoted microphase separation. Under stretching large domains are prone to orient with their long axis along tensile direction and thus a negative orientation of hard segments is observed. Meanwhile, decreased orientation of soft segments can also find its origin in the reduced crosslinking density provided by hard domains because of preferential association among hard segments in such a biomedical material. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 2198–2205, 2009
Poly(vinylpyrrolidone)‐based films grown on copper surfaces
Authors: De Amorim Alexandra Mara , Franzoi Ana Cristina , Oliveira Paula Nunes , Pires Alfredo Tibúrcio Nunes , Spinelli Almir , Bertolino José Roberto 
Published: October 2009

AbstractThe influence of molecular weight and the amount of the poly(vinylpyrrolidone) (PVP) on the growth of poly(vinylpyrrolidone)–based films on copper surfaces was studied by electrochemical, infrared and electronic spectroscopy, and thermogravimetric methods. Complex polymer/metal ions were deposited onto a copper surface, as the result of the electrochemically generated reaction of copper cations with PVP and SCN−, in sulfuric acid media. Spontaneous film growth on copper surfaces was generated and characterized as a Cu(II)/PVP/SCN− complex. Infrared spectra and thermal gravimetric curves of the films generated at + 0.7 V were compared with the chemically synthesized complex, and show the same patterns. The oxidation process can be described as: Cu(0)→Cu(I) and Cu(I)→Cu(II), and the copper complex formed at more positive potentials was characterized as Cu(II)/PVP/SCN−, with copper bonded to the oxygen atom of PVP and thiocyanate ligand N‐linked. This study focuses on the complex formation on a copper surface in acid media and its characterization through electrochemical and spontaneously generated reactions. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 2206–2214, 2009
Determination of pyridoxal‐5′‐phosphate (PLP)‐bonding sites in proteins: a peptide mass fingerprinting approach based on diagnostic tandem mass spectral features of PLP‐modified peptides
Authors: Simon Eric S. , Allison John 
Published: October 2009

AbstractPeptides modified by pyridoxal‐5′‐phosphate (PLP), linked to a lysine residue via reductive amination, exhibit distinct spectral characteristics in the collision‐induced dissociation (CID) tandem mass (MS/MS) spectra that are described here. The MS/MS spectra typically display two dominant peaks whose m/z values correspond to neutral losses of [H3PO4] (−98 Da) and the PLP moiety as [C8H10NO5P] (−231 Da) from the precursor peptide ion, respectively. Few other peaks are observed. Recognition of this distinct fragmentation behavior is imperative since determining sequences and sites of modifications relies on the formation of amide backbone cleavage products for subsequent interpretation via proteome database searching. Additionally, PLP‐modified peptides exhibit suppressed precursor ionization efficiency which diminishes their detection in complex mixtures. Presented here is a protocol which describes an enrichment strategy for PLP‐modified peptides combined with neutral loss screening and peptide mass fingerprinting to map the PLP‐bonding site in a known PLP‐dependent protein. This approach represents an efficient alternative to site‐directed mutagenesis which has been the traditional method used for PLP‐bonding site localization in proteins. Copyright © 2009 John Wiley & Sons, Ltd.