bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reactive desorption electrospray ionization for selective detection of the hydrolysis products of phosphonate esters
Authors: Song Yishu , Cooks R. Graham 
Published: July 2007

AbstractReactive desorption electrospray ionization (reactive DESI) is demonstrated to be a rapid and sensitive method for the direct detection of alkyl methylphosphonic acids, the hydrolysis products and metabolites of the chemical warfare (CW) agents VX (S‐2‐diisopropylaminoethyl‐O‐ethyl methylphosphonothiolate) and GB (sarin, isopropylmethyl phosphonofluoridate). Rapid and sensitive detection of these compounds is readily achieved by performing DESI from a solid surface; detection specificity is enhanced by implementation of a heterogeneous ion/molecule reaction using boric acid in the spray solvent. The reagent ion H2BO3− generated in the spray readily reacts with condensed‐phase alkyl MPA to form anionic adducts. The specificity of this chemical reaction, together with the characteristic fragmentation patterns of the reaction products, supplies a highly discriminatory detection method for methylphosphonic acid (MPA), ethylphosphonic acid (EMPA) and isopropyl methylphosphonic acid (IMPA) in complex matrices. Copyright © 2007 John Wiley & Sons, Ltd.
Establishment and characterization of an in vivo model for Epstein–Barr virus positive gastric carcinoma
Authors: Oh Sang Taek , Cha Jung‐Ho , Shin Dong‐Jik , Yoon Sungjoo Kim , Lee Suk Kyeong 
Published: July 2007

AbstractResearch regarding the role of the Epstein–Barr virus (EBV) in gastric carcinogenesis has been hampered by the absence of a suitable model system. SNU‐719 is a gastric carcinoma cell line naturally infected with EBV. This cell line developed tumors in nude mice approximately 40–56 days after inoculation. SNU‐719 also showed low serum dependency and anchorage independent growth in vitro. The developed tumors expressed EBERs, EBNA1, and LMP2A but not other EBV latent genes. Additionally, Qp was active and either mono‐ or bi‐clonal EBV genome was observed in the tumor tissues. Because the developed tumors retained characteristics of EBV‐associated gastric cancer, this cell line could serve as a useful in vivo system to investigate the tumorigenesis mechanism and treatment methods for this type of tumor. J. Med. Virol. 79:1343–1348, 2007. © Wiley‐Liss, Inc.
Amine‐Functionalized Polyacrylamide for Labeling and Crosslinking Purposes
Authors: Seiffert Sebastian , Oppermann Wilhelm 
Published: July 2007

AbstractFree radical copolymerization of acrylamide with N‐(3‐aminopropyl)‐methacrylamide yields water‐soluble polymers with randomly distributed pendent nucleophilic amine moieties. The copolymerization parameters were determined to be r1 = 0.49 and r2 = 0.85. A procedure which allows controlling the degree of functionalization and the molecular weight is described in detail. Copolymers with low amounts of functional groups were used to synthesize polymers with fluoresceine or rhodamine side groups as fluorescence labels. Furthermore, reaction of the amine moieties of the copolymers with glutaraldehyde under suitable conditions provides a way to generate polymer networks via random crosslinking of existent chains in a semi‐dilute solution.magnified image
Free Energy of Deformation of the Radius of Gyration in Semiflexible Chains
Authors: Cifra Peter , Bleha Tomáš 
Published: July 2007

AbstractThe distribution function P(S) of the radius of gyration S, the corresponding elastic free energy A(S) and the mean force $\left\langle f \right\rangle (S)$ were computed from simulations based on the wormlike chain (WLC) model. The relation of the S‐conjugated elastic functions to the analogous functions based on the chain vector R and their connection to the statistical‐mechanics ensembles was elucidated. Simulation data revealed that available analytical functions for P(S) fail to predict the behavior of semiflexible chains. When the power‐law function P(S) was used instead, the exponents sizeably raised with stiffness at chain expansion. The exponents deduced from elastic compression of a chain agreed fairly with the scaling exponents for chain confinement into a sphere.magnified image
Qualitative methodologies I: asking research questions with reflexive insight
Authors: Hale Elizabeth D. , Treharne Gareth J. , Kitas George D. 
Published: July 2007

AbstractThe purpose of this paper, the first of a series of two discussion pieces, is to introduce some of the issues in the debate surrounding qualitative research to the readers of Musculoskeletal Care. Recent issues of the Journal have seen an informative focus on quantitative methods and statistical analysis, and here we provide an equivalent introduction to semi‐structured interviewing and qualitative analysis in this series. In the qualitative tradition, we have tried to keep our discussion reflexive, transparent and contextualized within the history of the approach and the theoretical considerations that underlie it, including the origins, nature, methods and limits of the approach. We provide information that we hope is useful for readers with all levels of familiarity with qualitative research, building from an introduction to some basic assumptions and ethical issues. We also introduce one specific qualitative approach, interpretative phenomenological analysis, which researchers might wish to apply. In the accompanying paper in a subsequent issue of Musculoskeletal Care, we will describe the potential application of this approach. Copyright © 2007 John Wiley & Sons, Ltd.
Analysis of laterally loaded piles with rectangular cross sections embedded in layered soil
Authors: Basu D. , Salgado R. 
Published: July 2007

AbstractAn analysis is developed to determine the response of laterally loaded rectangular piles in layered elastic media. The differential equations governing the displacements of the pile–soil system are derived using variational principles. Closed‐form solutions of pile deflection, the slope of the deflected curve, the bending moment and the shear force profiles can be obtained by this method for the entire pile length. The input parameters needed for the analysis are the pile geometry and the elastic constants of the soil and pile. The new analysis allows insights into the lateral load response of square, rectangular and circular piles and how they compare. Copyright © 2007 John Wiley & Sons,
Ltd.
Association between prenatal pesticide exposures and the generation of leukemia‐associated T(8;21)
Authors: LaFiura Katherine M. , Bielawski Dawn M. , Posecion Norberto C. , Ostrea Enrique M. , Matherly Larry H. , Taub Jeffrey W. , Ge Yubin 
Published: July 2007

AbstractBackgroundThis study was designed to investigate the relationship between prenatal pesticide exposures and the generation of leukemia‐associated t(8;21)(q22;q22), one of the most common cytogenetic abnormalities in childhood acute myeloid leukemia (AML).ProcedureGas chromatography/mass spectrometry (GC/MS) was used to quantitatively detect different pesticides (propoxur and cypermethrin) in meconium from 49 newborn babies from the Philippines. The generation of t(8;21) was determined in the corresponding umbilical cord blood samples by detection of the AML1‐ETO fusion transcripts derived from t(8;21) using nested RT‐PCR. Levels for the AML1‐ETO fusion transcripts were quantitated by real‐time RT‐PCR in the t(8;21) positive cord blood samples. AML1‐ETO fusion transcript forms were characterized by RT‐PCR amplification and DNA sequencing.ResultsIn the present study using umbilical cord blood samples obtained from infants whose prenatal exposure to the pesticide, propoxur, was determined by meconium analysis, we showed that (i) incidence of t(8;21) in the exposed group was two‐fold higher than that in the unexposed group; and (ii) the levels for AML1‐ETO fusion transcripts resulting from t(8;21) positively correlated with propoxur concentrations in meconium. Similar heterogeneity in the fusion transcripts was detected in the t(8;21) positive cord blood samples as in our previous study with t(8;21) AML patients.ConclusionThese results further confirm the prenatal origin of t(8;21) and establish a significant correlation between prenatal pesticide exposures and the generation of t(8;21). They suggest that prenatal pesticide exposures may be causal factors for the generation of leukemia‐associated chromosomal translocations. Pediatr Blood Cancer 2007;49:624–628. © 2007 Wiley‐Liss, Inc.
Microstructural characterization of polymeric materials by small angle neutron scattering
Authors: Rogante Massimo , Lebedev Vassili T. 
Published: July 2007

AbstractSmall angle neutron scattering (SANS) is considered as a nondestructive technique adoptable for the microstructural characterization of polymeric materials. The possibility to substitute hydrogen for deuterium makes SANS an exclusive technique for investigating macromolecular structures in synthetic and biological polymers. The same method allows a visualization of polymer chains, because of a local contrast between small size ordered domains and amorphous matrix around. In this article, some theoretical bases are reported, and industrial applications of SANS in the polymers field are shown. In particular, SANS investigations of either monoethylene glycol‐based polyurethanes, or heat cured and laser machined organic resin microturbines as used for airflow sensing are described. Other examples are mentioned, moreover, showing the usefulness of SANS in characterizing polymers and confirming the improvement of this tool to a level of industrial applicability. POLYM. ENG. SCI., 47:1213–1219, 2007. © 2007 Society of Plastics Engineers
Capability of cationic water‐soluble polymers in conjunction with ultrafiltration membranes to remove arsenate ions
Authors: Rivas Bernabé L. , Carmen Aguirre María del , Pereira Eduardo , Moutet Jean‐Claude , Aman Eric S. 
Published: July 2007

AbstractArsenic is one of the most hazardous pollutants, and is present in water, mainly, as As(V) and As(III), and in its inorganic hydrolysis species. Great efforts have been made to develop effective removal techniques. One alternative is the use of water‐soluble polymers containing functional groups to remove these toxic species. This paper presents the synthesis and characterization (FT‐IR and 1H NMR spectroscopy, as well as thermogravimetry TG‐DSC) of two cationic water‐soluble polymers containing tetra alkylammonium groups, poly[2‐(acryloyloxy)ethyl]trimethylammonium chloride, and poly[2‐acryloyloxy)ethyl]trimethylammonium methyl sulfate (P(SAETA)). The arsenate retention properties were investigated using the liquid‐phase polymer‐based retention technique. The polymer structure and the exchangeable anions' nature have been shown to be two important variables in the removal efficiency of arsenate anions from aqueous solutions. Both investigated polymers were found to efficiently remove HAsO42− species from an aqueous media, with pH ranging from 6 to 8. The exchange of methyl sulfate for the chloride anion on P(SAETA) improved arsenate ion retention ability. The modification of ionic strength by Na2SO4 addition induced a significant decrease in the cationic polymer's arsenate retention properties. The polymers' retention properties were not studied using real samples. POLYM. ENG. SCI., 47:1256–1261, 2007. © 2007 Society of Plastics Engineers
Controlled free radical photopolymerization of styrene initiated by trithiocarbonate
Authors: Ran Rong , Wan Tao , Gao Tao , Gao Jian , Chen Zhi 
Published: July 2007

AbstractDensity functional theory calculations are reported for prediction of the trends in CS bond dissociation energies and atomic spin densities for radicals using S,S′‐bis(α,α′‐dimethyl‐α‐acetic acid) trithiocarbonate (TTCA) and bis(2‐oxo‐2‐phenylethyl) trithiocarbonate (TTCB) as reversible addition fragmentation chain transfer (RAFT) reagents. The calculations predict that the value of the CS bond length (1.865 Å) of TTCA is longer than that (1.826 Å) of TTCB, and TTCA is more effective for the polymerization of styrene (St) compared to TTCB as predicted by density functional theory. In photopolymerizations, pseudo‐first‐order kinetics were confirmed for TTCB‐mediated photopolymerization of St due to the linear increase of ln([M]0/[M]) up to about 28% conversion, suggesting the living characteristics behavior of the photopolymerization of St in the presence of TTCB. For both TTCA and TTCB the polydispersities change with increasing conversion in the range 1.10–1.45, typical for RAFT‐prepared (co)polymers and well below the theoretical lower limit of 1.50 for a normal free radical polymerization. In addition, the triblock copolymer polystyrene‐block‐poly(butyl acrylate)‐block‐polystyrene (PSPBAPS) was successfully prepared, with very good control over molecular weight and narrow polydispersity (Mw/Mn = 1.45), using PSSC(S)SPS as macro‐photoinitiator under UV irradiation at room temperature. This indicated that this reversible and valid strategy led to a better controlled block copolymer with defined structures. Copyright © 2007 Society of Chemical Industry
The effect of doubled CO2 and model basic state biases on the monsoon‐ENSO system. I: Mean response and interannual variability
Authors: Turner A. G. , Inness P. M. , Slingo J. M. 
Published: July 2007

AbstractThe impact of doubled CO2 concentration on the Asian summer monsoon is studied using a coupled ocean‐atmosphere model. Both the mean seasonal precipitation and interannual monsoon variability are found to increase in the future climate scenario presented. Systematic biases in current climate simulations of the coupled system prevent accurate representation of the monsoon‐ENSO teleconnection, of prime importance for seasonal prediction and for determining monsoon interannual variability. By applying seasonally varying heat flux adjustments to the tropical Pacific and Indian Ocean surface in the future climate simulation, some assessment can be made of the impact of systematic model biases on future climate predictions. In simulations where the flux adjustments are implemented, the response to climate change is magnified, with the suggestion that systematic biases may be masking the true impact of increased greenhouse gas forcing. The teleconnection between ENSO and the Asian summer monsoon remains robust in the future climate, although the Indo‐Pacific takes on more of a biennial character for long periods of the flux‐adjusted simulation. Assessing the teleconnection across interdecadal timescales shows wide variations in its amplitude, despite the absence of external forcing. This suggests that recent changes in the observed record cannot be distinguished from internal variations and as such are not necessarily related to climate change. Copyright © 2007 Royal Meteorological Society
Towards a possible ab initio molecular mechanics. Transferability of density matrix elements
Authors: Tchougréeff A. L. , Tokmachev A. M. , Mayer I. 
Published: July 2007

AbstractMolecular structures are characterized by a large degree of additivity and transferability of various intramolecular interactions determining the shape and energetics of molecules. This property is constantly utilized by the different “molecular mechanics” (MM) schemes which allow one to obtain quite reliable molecular geometries and relative energy values for a wide range of molecular systems, which is especially remarkabke in the light of the simplicity of the assumptions made. Numerous MM schemes presented in the literature use different sets of parameters (force fields, etc.), which are adjusted empirically. The known success of MM models poses two important questions: first, one wishes to understand why do they work at all, and, second, one would like to develop schemes, in which the parameters of MM can be determined theoretically. Such an analysis could also give some deeper insight permitting to predict whether the given MM scheme is expected to be successful if applied to the class of problems actually at hand. From a more pragmatic point of view, having a bridge connecting a quantum mechanical (QM) description of molecular structure with a classical moldel (MM) can help to improve hybrid QM/MM methods by providing a systematic derivation of the form of the junction between the subsystems treated by MM and QM, respectively and by giving a priori estimates of the junction parameters. Our previous studies based on the semiempirical quantum chemical Hamiltonians of MINDO and MNDO types permitted us to draw the conclusion that the success of MM can indeed be understood on the basis of quantum mechanics. The analysis of the geminal‐type wave functions constructed by making use of oriented hybrid orbitals showed that the parameters of the wave function and the energy contributions of the individual bonds are indeed well transferable, in good agreement with the simple chemical picture of the systems studied. It seems to be desirable to develop a similar analysis also at the ab initio level of the theory, because that would connect together the chemical and physical description of molecules and explain the observed transferability of molecular interactions more rigorously than semiempirical theories can do it. On the other hand this treatment might be also useful for developing QM/MM junctions in the cases when the QM part of the systems are described at the ab initio level. We report here results of the first step of this analysis: the geminal parameters expressed in a symmetrically orthogonalized optimized minimal basis set exhibit a degree of stability similar to that observed in the semiempirical case. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2007
Surface‐activated chemical ionization ion trap mass spectrometry for the analysis of cocaine and benzoylecgonine in hair after extraction and sample dilution
Authors: Cristoni Simone , Basso Elisa , Gerthoux Piermario , Mocarelli Paolo , Gonella Elisabetta , Brambilla Maura , Crotti Sara , Bernardi Luigi Rossi 
Published: July 2007

AbstractSurface‐activated chemical ionization (SACI) was employed for the analysis of cocaine and its metabolite, benzoylecgonine, extracted from hair. Following decontamination and acid hydrolysis procedures on the hair sample, the sample solution was diluted (1:10) and directly analyzed by liquid chromatography/surface‐activated chemical ionization multiple collisional stage single reaction monitoring mass spectrometry (LC/SACI‐MS3‐SRM) without solid‐phase extraction (SPE) pre‐purification and concentration procedures. To increase the selectivity of the method, MS3 was chosen instead of the less selective MS/MS. This data was compared with that achieved using gas chromatography/mass spectrometry (GC/MS), the reference method used by the Italian Government Institute of Health protocol. The limits of detection (LODs) were 0.003 ng/(mg hair) for cocaine and 0.02 ng/(mg hair) for benzoylecgonine and the limits of quantitation (LOQs) were 0.01 ng/(mg hair) for cocaine and 0.04 ng/(mg hair) for benzoylecgonine. The squared correlation coefficient (R2) of the calibration curve was 0.9887–0.9980 for cocaine and 0.9987–0.9997 for benzoylecgonine. The percent accuracy error was 2–5% for both cocaine and benzoylecgonine using the LC/SACI‐MS3‐SRM approach, whereas it was higher for benzoylecgonine (20–25%) using the LC/SACI‐MS/MS‐SRM approach compared with the GC/MS data due to hair matrix contamination. In both cases, high precision was achieved (1–3% precision error), which confirmed the stability of the developed methods. Copyright © 2007 John Wiley & Sons, Ltd.
Personal information of adolescents on the Internet: A quantitative content analysis of MySpace
Authors: Hinduja Sameer , Patchin Justin W. 
Published: July 2007

ABSTRACTMany youth have recently embraced online social networking sites such as MySpace (myspace.com) to meet their social and relational needs. While manifold benefits stem from participating in such web‐based environments, the popular media has been quick to demonize MySpace even though an exponentially small proportion of its users have been victimized due to irresponsible or naïve usage of the technology it affords. Major concerns revolve around the possibility of sexual predators and pedophiles finding and then assaulting adolescents who carelessly or unwittingly reveal identifiable information on their personal profile pages. The current study sought to empirically ascertain the type of information youth are publicly posting through an extensive content analysis of randomly sampled MySpace profile pages. Among other findings, 8.8% revealed their full name, 57% included a picture, 27.8% listed their school, and 0.3% provided their telephone number. When considered in its proper context, these results indicate that the problem of personal information disclosure on MySpace may not be as widespread as many assume, and that the overwhelming majority of adolescents are responsibly using the web site. Implications for Internet safety among adolescents and future research regarding adolescent Internet use are discussed.
Examination of the interaction between peripheral lumiracoxib and opioids on the 1% formalin test in rats
Authors: Ortiz Mario I. , Castañeda‐Hernández Gilberto 
Published: July 2007

AbstractIt has been shown that the association of non‐steroidal anti‐inflammatory drugs (NSAIDs) with opioid analgesic agents can increase their antinociceptive activity, allowing the use of lower doses and thus limiting side effects. Therefore, the aim of the present study was to examine the possible pharmacological interaction between lumiracoxib and codeine or nalbuphine at the local peripheral level in the rat using the 1% formalin test and isobolographic analysis. Lumiracoxib, codeine, nalbuphine or fixed‐dose ratios lumiracoxib—codeine or lumiracoxib—nalbuphine combinations were administrated locally in the formalin‐injured paw and the antinociceptive effect was evaluated using the 1% formalin test. All treatments produced a dose‐dependent antinociceptive effect. ED40values were estimated for the individual drugs and an isobologram was constructed. The derived theoretical ED40's for the lumiracoxib—codeine and lumiracoxib—nalbuphine combinations were 423.4±31.3μg/paw and 310.9±24.2μg/paw, respectively, being significantly higher than the actually observed experimental ED40values, 233.2±30.9μg/paw and 132.7±11.6μg/paw, respectively. These results correspond to a synergistic interaction between lumiracoxib and opioids at the local peripheral level, potency being about two times higher with regard to that expected from the addition of the effects of the individual drugs. Data suggest that low doses of the lumiracoxib—opioids combination can interact synergistically at the peripheral level and therefore this drug association may represent a therapeutic advantage for the clinical treatment of inflammatory pain.
Wider application of prolonged nasotracheal intubation
Authors: Bos C. E. , Berkovits R. N. P. , Struben W. H. 
Published: July 2007

SummaryENCOURAGED by reports of the treatment of laryngotracheal obstruction with nasotracheal intubation (N.T.I.), we began in 1965 to use this method in patients presenting such problems. At the outset we decided to use unsterilized and siliconized P.V.C. tubes in order to avoid toxicity and to provide ‘boundary lubrication’. Some preliminary experiments on these matters are presented.We found that by using this approach the range of indications for N.T.I, could be greatly extended. Forty-three out of forty-six patients, most of whom had chronic narrowings, were treated satisfactorily. The fact that eleven patients with obstructions caused by previous endotracheal intubation were cured by further intubation is noteworthy.