bluuebunny/crossref_metadata_2025_split huggingface dataset:
Trifluoro‐3‐hydroxy‐1H‐indazolecarboxylic Acids and Esters from Perfluorinated Benzenedicarboxylic Acids
Authors: Pérez Medina Carlos , López Concepción , Claramunt Rosa M. , Elguero José 
Published: December 2009

AbstractTwelve new 3‐hydroxyindazoles, each bearing three fluorine substituents and a CO2R group (R = H, CH3, C2H5) distributed around its 4‐, 5‐, 6‐, and 7‐positions, have been synthesized. They were studied by NMR in solution (1H, 13C, 15N, 19F) and in the solid state (13C, 15N). In solution, all of them are 3‐hydroxy tautomers: the a form. In the solid state, although the 3‐hydroxy tautomers are still the most frequent, there are some cases of indazolin‐3‐ones – the b form – and one example (12ab) of the very rare case in which both tautomers are present.
A dual‐weighted trust‐region adaptive POD 4D‐VAR applied to a finite‐element shallow‐water equations model
Authors: Chen X. , Navon I. M. , Fang F. 
Published: December 2009

AbstractWe consider a limited‐area finite‐element discretization of the shallow‐water equations model. Our purpose in this paper is to solve an inverse problem for the above model controlling its initial conditions in presence of observations being assimilated in a time interval (window of assimilation). We then attempt to obtain a reduced‐order model of the above inverse problem, based on proper orthogonal decomposition (POD), referred to as POD 4‐D VAR. Different approaches of POD implementation of the reduced inverse problem are compared, including a dual‐weighed method for snapshot selection coupled with a trust‐region POD approach. Numerical results obtained point to an improved accuracy in all metrics tested when dual‐weighing choice of snapshots is combined with POD adaptivity of the trust‐region type. Results of ad‐hoc adaptivity of the POD 4‐D VAR turn out to yield less accurate results than trust‐region POD when compared with high‐fidelity model. Directions of future research are finally outlined. Copyright © 2009 John Wiley & Sons, Ltd.
Cell face velocity alternatives in a structured colocated grid for the unsteady Navier–Stokes equations
Authors: Pascau A. 
Published: December 2009

AbstractThe use of a colocated variable arrangement for the numerical solution of fluid flow is becoming more and more popular due to its coding simplicity. The inherent decoupling of the pressure and velocity fields in this arrangement can be handled via a special interpolation procedure for the calculation of the cell face velocity named pressure‐weighted interpolation method (PWIM) (AIAA J. 1983; 21(11):1525–1532). In this paper a discussion on the alternatives to extend PWIM to unsteady flows is presented along with a very simple criterion to ascertain if a given interpolation practice will produce steady results that are relaxation dependent or time step dependent. Following this criterion it will be shown that some prior schemes presented as time step independent are actually not, although by using special interpolations can be readily adapted to be. A systematic way of deriving different cell face velocity expressions will be presented and new formulae free of Δt dependence will be derived. Several computational exercises will accompany the theoretical discussion to support our claims. Copyright © 2009 John Wiley & Sons, Ltd.
Sustained low‐dose growth hormone therapy optimizes bioactive insulin‐like growth factor‐I level and may enhance CD4 T‐cell number in HIV infection
Authors: Andersen Ove , Hansen Birgitte Rønde , Troensegaard William , Flyvbjerg Allan , Madsbad Sten , Ørskov Hans , Nielsen Jens Ole , Iversen Johan , Haugaard Steen B. 
Published: December 2009

AbstractHigh‐dose recombinant human growth hormone (rhGH) (2–6 mg/day) regimes may facilitate T‐cell restoration in patients infected with human immunodeficiency virus (HIV) on highly active antiretroviral therapy (HAART). However, high‐dose rhGH regimens increase insulin‐like growth factor‐I (IGF‐I) to supra‐physiological levels associated with severe side effects. The present study investigated whether lower doses of rhGH may improve T‐cell restoration in patients infected with HIV following an expedient response of total and bioactive (i.e., free) IGF‐I. A previous 16‐week pilot‐study included six HIV‐infected patients on stable HAART to receive rhGH 0.7 mg/day, which increased total (+117%, P < 0.01) and free (+155%, P < 0.01) IGF‐I levels. The study was extended to examine whether continuous use of low‐dose rhGH (0.7 mg/day until week 60; 0.4 mg/day from week 60 to week 140) would maintain expedient IGF‐I levels and improve CD4 T‐cell response. Total and free IGF‐I increased at week 36 (+97%, P < 0.01 and +125%, P < 0.01, respectively) and week 60 (+77%, P = 0.01 and +125%, P < 0.01) compared to baseline levels (161 ± 15 and 0.75 ± 0.11 µg/L). CD4 T‐cell number increased at week 36 (+15%, P < 0.05) and week 60 (+31%, P = 0.01) compared to baseline levels (456 ± 55 cells/µL). Following rhGH dose reduction, total IGF‐I and CD4 T‐cell number remained increased at week 88 (+44%, P = 0.01 and +33%, P < 0.01) and week 140 (+46%, P = 0.07 and +36%, P = 0.02) compared to baseline levels. These data support the notion that low‐dose rhGH regimens may increase expediently total and bioactive IGF‐I and improve T‐cell restoration in patients infected with HIV on HAART. J. Med. Virol. 82:197–205, 2010. © 2009 Wiley‐Liss, Inc.
Geographic distribution of hepatitis C virus genotype 6 subtypes in Thailand
Authors: Akkarathamrongsin Srunthron , Praianantathavorn Kesmanee , Hacharoen Nisachol , Theamboonlers Apiradee , Tangkijvanich Pisit , Tanaka Yasuhito , Mizokami Masashi , Poovorawan Yong 
Published: December 2009

AbstractThe nucleotide sequence of hepatitis C virus (HCV) genotype 6 found mostly in south China and south‐east Asia, displays profound genetic diversity. The aim of this study to determine the genetic variability of HCV genotype 6 (HCV‐6) in Thailand and locate the subtype distribution of genotype 6 in various geographic areas. Four hundred nineteen anti‐HCV positive serum samples were collected from patients residing in ‐ the central part of the country. HCV RNA positive samples based on reverse transcriptase‐ polymerase chain reaction (RT‐PCR) of the 5′UTR were amplified with primers specific for the core and NS5B regions. Nucleotide sequences of both regions were analyzed for the genotype by phylogenetic analysis. To determine geographic distribution of HCV‐6 subtypes, a search of the international database on subtype distribution in the respective countries was conducted. Among 375 HCV RNA positive samples, 71 had HCV‐6 based on phylogenetic analysis of partial core and NS5B regions. The subtype distribution in order of predominance was 6f (56%), 6n (22%), 6i (11%), 6j (10%), and 6e (1%). Among the 13 countries with different subtypes of HCV‐6, most sequences have been reported from Vietnam. Subtype 6f was found exclusively in Thailand where five distinct HCV‐6 subtypes are circulating. HCV‐6, which is endemic in south China and south‐east Asia, displays profound genetic diversity and may have evolved over a considerable period of time. J. Med. Virol. 82:257–262, 2010. © 2009 Wiley‐Liss, Inc.
Sequence variations of the VP1 gene of Polyomavirus hominis 1 among Bulgarians
Authors: Slavov Svetoslav , Tsekov Iliya , Kalvatchev Zlatko 
Published: December 2009

AbstractPolyomavirus hominis 1 (BK virus, BKV) is an important pathogen in the field of transplantation medicine. BKV reactivation among renal‐transplant recipients could cause BK associated nephropathy, which has unfavorable prognosis and is a cause for graft rejection. It is not clear why only few transplanted patients develop BK associated nephropathy while most exhibit asymptomatic viruria. One of the possible reasons lies in the mutations of the VP1 gene, encoding the main structural protein, bearing important determinants for the recognition of specific cellular receptors. The change of amino acid sequence could result in altered pathogenicity of BKV. The amplified sequences of BK in this research were from urines of patients with various clinical conditions along with healthy individuals. Nevertheless the sequence analysis which was undertaken did not show correlation between the viral genotype and the clinical condition. It was demonstrated that the most common BKV genotype in Bulgaria is genotype I and that the strains common in Bulgaria (genotypes I and IV) have typical European origin. Most of the sequenced BKV DNA samples (8/10) were correlated with the highest degree of similarity (81%) to the subcluster Ib. A specific place among the samples is taken by Pr‐9, amplified from the urine of a pregnant woman that has a different evolutionary origins and might establish the beginning of a new distinct BKV strain. J. Med. Virol. 82:325–330, 2010. © 2009 Wiley‐Liss, Inc.
Raman spectroscopic study of the hydrogen‐arsenate mineral pharmacolite Ca(AsO3OH)·2H2O—implications for aquifer and sediment remediation
Authors: Frost Ray L. , Bahfenne Silmarilly , Čejka Jiří , Sejkora Jiří , Plášil Jakub , Palmer Sara J. 
Published: December 2009

AbstractThe removal of arsenate anions from aqueous media, sediments and wasted soils is of environmental significance. The reaction of gypsum with the arsenate anion results in pharmacolite mineral formation, together with related minerals. Raman and infrared (IR) spectroscopy have been used to study the mineral pharmacolite Ca(AsO3OH)· 2H2O. The mineral is characterised by an intense Raman band at 865 cm−1 assigned to the ν1 (AsO3)2− symmetric stretching mode. The equivalent IR band is found at 864 cm−1. The low‐intensity Raman bands in the range from 844 to 886 cm−1 provide evidence for ν3 (AsO3) antisymmetric stretching vibrations. A series of overlapping bands in the 300‐450 cm−1 region are attributed to ν2 and ν4 (AsO3) bending modes. Prominent Raman bands at around 3187 cm−1 are assigned to the OH stretching vibrations of hydrogen‐bonded water molecules and the two sharp bands at 3425 and 3526 cm−1 to the OH stretching vibrations of only weakly hydrogen‐bonded hydroxyls in (AsO3OH)2− units. Copyright © 2009 John Wiley & Sons, Ltd.
Varietal characterization of hop (Humulus lupulus L.) by GC–MS analysis of hop cone extracts
Authors: Shellie Robert A. , Poynter Samuel D. H. , Li Jianfeng , Gathercole Jessica L. , Whittock Simon P. , Koutoulis Anthony 
Published: December 2009

AbstractAn approach is described for use in the varietal characterization of hop (Humulus lupulus L.) varieties. The study focuses on commercial hop varieties and was timed to coincide with the 2008 commercial hop harvest in Tasmania, Australia. Analysis of hop extracts was performed using GC–MS. A 60 m capillary column was employed to increase efficiency to permit the use of a quadrupole mass spectrometer in place of a time of flight mass spectrometer that is more commonly used for this type of analysis. A set of characterization functions were derived from discriminant analysis which were highly suitable for varietal characterization of the eight commercial varieties included in the study, namely Willamette, Victoria, Pride of Ringwood, Cascade, Southern Hallertau, Millennium, Southern Saaz, and Super Pride.
Analytical food control does not live up to expectations – What to do?
Authors: Grob Koni 
Published: December 2009

AbstractThere are good reasons to devote a special issue to food analysis. First of all it is a challenging field, extremely wide and complex. There is a need for many more methods and plenty of room for technical improvements, as will be shown in the articles presented in this issue. However, there are also structural problems to be discussed, which are as challenging as the technical issues. Analytical chemistry is primarily a tool and its development is directly linked to the success of the service it provides and the reputation it has. We analysts must, therefore, have an interest in the success of the tool we are developing, structural aspects of our profession, financial issues and perhaps even “politics”.
Coarse‐grained molecular dynamics modeling of DNA–carbon nanotube complexes
Authors: Zou Jian , Liang Wentao , Zhang Sulin 
Published: December 2009

AbstractWe present a coarse‐grained method to study the energetics and morphologies of DNA–carbon nanotube (DNA‐CNT) complexes in aqueous environment. In this method, we adopt an existing coarse‐grained DNA model in which each nucleotide is coarse‐grained by two interaction sites, one for the phosphate and sugar groups and the other for the base group. The interaction potentials between DNA sites and the carbon atoms on a CNT are parameterized through all‐atom molecular dynamics (MD) simulations. The water molecules are treated implicitly using Langevin dynamics. The coarse‐grained DNA‐CNT model significantly improves the computational affordability, while captures the essential dynamics of DNA‐CNT interactions observed from all‐atom MD simulations. The coarse‐grained method enables us to efficiently simulate adhesion, encapsulation, and wrapping processes of a single‐stranded DNA molecule around CNTs. The simulation results agree with those obtained by all‐atom MD simulations in several aspects. Our coarse‐grained simulations provide useful guidelines in positioning DNA molecules on a CNT surface or graphene substrate in single‐molecule experimental studies. Copyright © 2009 John Wiley & Sons, Ltd.
Methylthioadenosine phosphorylase and activated insulin‐like growth factor‐1 receptor/insulin receptor: potential therapeutic targets in chordoma
Authors: Sommer Josh , Itani Doha M , Homlar Kelly C , Keedy Vicki L , Halpern Jennifer L , Holt Ginger E , Schwartz Herbert S , Coffin Cheryl M , Kelley Michael J , Cates Justin MM 
Published: December 2009

AbstractCurrently there is no effective chemotherapy for chordoma. Recent studies report co‐expression of insulin‐like growth factor‐1 receptor (IGF1R) and its cognate ligand in chordoma, but it is unknown whether this receptor tyrosine kinase is activated in these tumours. Additionally, genetic studies have confirmed frequent deletions of chromosome 9p in chordomas, which encompasses the cyclin‐dependent kinase inhibitor 2A (CDKN2A) locus. Another gene in this region, methylthioadenosine phosphorylase (MTAP), is an essential enzyme of the purine salvage pathway and has therapeutic relevance because MTAP‐deficient cells are particularly sensitive to inhibitors of de novo purine synthesis. We investigated whether these pathways might be potential therapeutic targets for chordoma. Paraffin‐embedded tissue samples from 30 chordomas were analysed by immunohistochemistry for expression of the phosphorylated isoforms of IGF1R or the insulin receptor (pIGF1R/pIR) and selected downstream signalling molecules, including BCL2‐associated agonist of cell death protein (BAD). Expression of CDKN2A and MTAP proteins was also assessed. Skeletal chondrosarcomas, benign notochordal cell tumours, and fetal notochord were studied for comparison. Phosphorylated IGF1R/IR was detected in 41% of chordomas, together with activated downstream signalling molecules, and pIGF1R/pIR was absent in benign notochordal cell tumours and fetal notochord. Thirty‐nine per cent of chordomas were negative for MTAP immunoreactivity. Patients with pIGF1R/pIR‐positive tumours showed significantly decreased median disease‐free survival in multivariate survival analysis (p = 0.036), whereas phosphorylation of BAD at serine‐99 was found to be associated with a favourable prognosis (p = 0.002). Approximately 40% of chordomas demonstrate evidence of activation of the IGF1R/IR signalling pathway or loss of a key enzyme in the purine salvage pathway. Aberrant signalling cascades and disrupted metabolic pathways such as these may represent opportunities for novel targeted therapeutic approaches for the treatment of chordoma. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Adjuvant effects of ambient particulate matter monitored by proteomics of bronchoalveolar lavage fluid
Authors: Kang Xuedong , Li Ning , Wang Meiying , Boontheung Pinmanee , Sioutas Constantinos , Harkema Jack R. , Bramble Lori A. , Nel Andre E. , Loo Joseph A. 
Published: December 2009

AbstractAmbient particulate matter (PM) from air pollution is associated with exacerbation of asthma. The immunological basis for the adjuvant effects of PM is still not well understood. The generation of ROS and the resulting oxidative stress has been identified as one of the major mechanisms. Using a new intranasal sensitization model in which ambient PM is used as an adjuvant to enhance allergic inflammation (Li et al., Environ. Health Perspect. 2009, 117, 1116–1123), a proteomics approach was applied to study the adjuvant effects of ambient PM. The enhanced in vivo adjuvant effect of ultrafine particles correlates with a higher in vitro oxidant potential and a higher content of redox‐cycling organic chemicals. Bronchoalveolar lavage fluid proteins from normal and sensitized mice were resolved by 2‐DE, and identified by MS. Polymeric immunoglobulin receptor, complement C3, neutrophil gelatinase‐associated lipocalin, chitinase 3‐like protein 3, chitinase 3‐like protein 4, and acidic mammalian chitinase demonstrated significantly enhanced up‐regulation by UFP with a polycyclic aromatic hydrocarbon content and a higher oxidant potential. These proteins may be the important specific elements targeted by PM in air pollution through the ability to generate ROS in the immune system, and may be involved in allergen sensitization and asthma pathogenesis.
Kinetic model of reversible addition‐fragmentation chain transfer polymerization in microemulsions
Authors: O'Donnell Jennifer M. , Kaler Eric W. 
Published: December 2009

AbstractA simplified kinetic model for RAFT microemulsion polymerization has been developed to facilitate the investigation of the effects of slow fragmentation of the intermediate macro‐RAFT radical, termination reactions, and diffusion rate of the chain transfer agent to the locus of polymerization on the control of the polymerization and the rate of monomer conversion. This simplified model captures the experimentally observed decrease in the rate of polymerization, and the shift of the rate maximum to conversions less than the 39% conversion predicted by the Morgan model for uncontrolled microemulsion polymerizations. The model shows that the short, but finite, lifetime of the intermediate macro‐RAFT radical (1.3 × 10−4–1.3 × 10−2 s) causes the observed rate retardation in RAFT microemulsion polymerizations of butyl acrylate with the chain transfer agent methyl‐2‐(O‐ethylxanthyl)propionate. The calculated magnitude of the fragmentation rate constant (kf = 4.0 × 101–4.0 × 103 s−1) is greater than the literature values for bulk RAFT polymerizations that only consider slow fragmentation of the macro‐RAFT radical and not termination (kf = 10−2 s−1). This is consistent with the finding that slow fragmentation promotes biradical termination in RAFT microemulsion polymerizations. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 604–613, 2010
Synthesis and properties of phenothiazylene vinylene‐based polymers: New organic semiconductors for field‐effect transistors and solar cells
Authors: Son Seon‐Kyoung , Choi Yoon‐Suk , Lee Woo‐Hyung , Hong Yongtaek , Kim Jae‐Ryoung , Shin Won‐Suk , Moon Sang‐Jin , Hwang Do‐Hoon , Kang In‐Nam 
Published: December 2009

AbstractA series of new phenothiazylene vinylene‐based semiconducting polymers, poly[3,7‐(4′‐dodecyloxyphenyl)phenothiazylene vinylene] (P1), poly[3,7‐(4′‐dodecyloxyphenyl)phenothiazylene vinylene‐alt‐1,4‐phenylene vinylene] (P2), and poly[3,7‐(4′‐dodecyloxyphenyl)phenothiazylene vinylene‐alt‐2,5‐thienylene vinylene] (P3), have been synthesized via a Horner‐Emmons reaction. FTIR and 1H NMR spectroscopies confirmed that the configurations of the vinylene groups in the polymers were all‐trans (E). The weight‐averaged molecular weights (Mw) of P1, P2, and P3 were found to be 27,000, 22,000, and 29,000, with polydispersity indices of 1.91, 2.05, and 2.25, respectively. The thermograms for P1, P2, and P3 each contained only a broad glass transition, at 129, 167, and 155 °C, respectively, without the observation of melting features. UV–visible absorption spectra of the polymers showed two strong absorption bands in the ranges 315–370 nm and 450–500 nm, which arose from absorptions of the phenothiazine segments and the conjugated main chains. Solution‐processed field‐effect transistors fabricated from these polymers showed p‐type organic thin‐film transistor characteristics. The field‐effect mobilities of P1, P2, and P3 were measured to be 1.0 × 10−4, 3.6 × 10−5, and 1.0 × 10−3 cm2 V−1 s−1, respectively, and the on/off ratios were in the order of 102 for P1 and P2, and 103 for P3. Atomic force microscopy and X‐ray diffraction analysis of thin films of the polymers show that they have amorphous structures. A photovoltaic device in which a P3/PC71BM (1/5) blend film was used as the active layer exhibited an open‐circuit voltage (VOC) of 0.42 V, a short circuit current (JSC) of 5.17 mA cm−2, a fill factor of 0.35, and a power conversion efficiency of 0.76% under AM 1.5 G (100 mW cm−2) illumination. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 635–646, 2010
Influence of the Air Humidity on the Reduction of Bacillus Spores in a Defined Environment at Atmospheric Pressure Using a Dielectric Barrier Surface Discharge
Authors: Hähnel Marcel , von Woedtke Thomas , Weltmann Klaus‐Dieter 
Published: December 2009

AbstractFrom literature different plasma species are known for their possibility to inactivate microorganisms. Most studies report on the inactivation of germs by UV light emitted from rare gas discharges like plasma‐jets or low pressure discharges or disruption of cell membranes due to charging effects.Our aim was to show the influence of air humidity and active plasma power in a simple atmospheric pressure dielectric barrier surface discharge on the reduction of Bacillus atrophaeus spores within a few minutes of treatment time. The plasma treatment time was varied at humidity levels between 0 and 70% relative moisture with a distance of 0.6 mm between the dielectric barrier and test strip. The obtained results have shown an influence of the air humidity on the spore inactivation rate which has been reached by plasma treatment. The plasma does not emit a significant amount of UV light below 320 nm. From these results the role of reactive species, especially the effect of hydroxyl radicals, is discussed.magnified image
Degradation of Triacetone Triperoxide (TATP) Using Mechanically Alloyed Mg/Pd
Authors: Fidler Albo Rebecca L. , Legron Tamra , Gittings Michael J. , Elie Mark R. , Holland Saitta Erin , Sigman Michael E. , Geiger Cherie L. , Clausen Christian 
Published: December 2009

AbstractA heterogenous catalytic system consisting of mechanically alloyed Mg/Pd particles has been used to degrade the peroxide explosive, triacetone triperoxide (TATP). The degradation of the TATP with the Mg/Pd particles (half life of 1.2×101 min) was compared to the degradation with microscale Mg particles (half life of 1.7×103 min) and 10% Pd on activated carbon (half life of 8.7×102 min). Combining the Mg and Pd on carbon (Pd/C) through a mechanical alloying process is shown to produce reactive particles that can be used to degrade TATP. The major product of the degradation of TATP with mechanically alloyed Mg/Pd particles was acetone. A material balance for carbon was also calculated for the degradation reaction with 94±5% (mean±standard deviation) of the TATP carbons accounted for in the production of acetone.