bluuebunny/crossref_metadata_2025_split huggingface dataset:
Biological activity of probable/possible high‐risk human papillomavirus types in cervical cancer
Authors: Halec Gordana , Schmitt Markus , Dondog Bolormaa , Sharkhuu Enkhtuya , Wentzensen Nicolas , Gheit Tarik , Tommasino Massimo , Kommoss Friedrich , Bosch Franz X. , Franceschi Silvia , Clifford Gary , Gissmann Lutz , Pawlita Michael 
Published: April 2012

AbstractJudging the carcinogenicity of human papillomavirus (HPV) types rarely found in cervical cancer (CxCa) is hindered by lack of studies of their biological activity in cancer tissues. To asses transcriptional activity of HPV types, we have developed ultra‐short amplimer, splice‐site specific, E6*I mRNA RT‐PCR assays for 12 high‐risk (HR)‐HPV (IARC Group 1) and eight probable/possible high‐risk (pHR)‐HPV types (IARC Group 2A/B carcinogens). Previously unreported E6*I splice sites of the six pHR‐HPV types 26, 53, 67, 70, 73 and 82 were identified by cloning and sequencing. We analyzed 97 formalin‐fixed paraffin‐embedded (FFPE) Mongolian CxCa biopsies for presence of HPV DNA by two sensitive genotyping assays, for E6*I transcripts of all HR‐/pHR‐HPV types identified and for expression of HPV surrogate markers p16INK4a, pRb and p53. E6*I of at least one HR‐/pHR‐HPV was expressed in 94 (98%) of cancer tissues including seven with pHR‐HPV types 26, 66, 70 or 82 as single transcribed types. Fifty‐eight of E6*I mRNA transcribing cases were analyzable by immunohistochemistry and displayed p16INK4a overexpression in 57 (98%), pRb downregulation in 56 (97%) and p53 downregulation in 36 (62%) tissues. The newly developed E6*I mRNA RT‐PCR assays appeared to be highly sensitive method to analyze HPV transcription in FFPE materials. Our finding of viral oncogene transcription of pHR‐HPV types 26, 66, 70 and 82 in cervical tumors, in the absence of any other transcriptionally active HR‐type and with p16INK4a overexpression and pRb downregulation, may support a reassessment of the carcinogenicity classification of these pHR‐HPV types.
Comparison of the electronic structure of different perylene‐based dye‐aggregates
Authors: Settels Volker , Liu Wenlan , Pflaum Jens , Fink Reinhold F. , Engels Bernd 
Published: April 2012

AbstractAggregates of functionalized polycyclic aromatic molecules like perylene derivatives differ in important optoelectronic properties such as absorption and emission spectra or exciton diffusion lengths. Although those differences are well known, it is not fully understood if they are caused by variations in the geometrical orientation of the molecules within the aggregates, variations in the electronic structures of the dye aggregates or interplay of both. As this knowledge is of interest for the development of materials with optimized functionalities, we investigate this question by comparing the electronic structures of dimer systems of representative perylene‐based chromophores. The study comprises dimers of perylene, 3,4,9,10‐perylene tetracarboxylic acid bisimide (PBI), 3,4,9,10‐perylene tetracarboxylic acid dianhydride (PTCDA), and diindeno perylene (DIP). Potential energy curves (PECs) and characters of those electronic states are investigated which determine the optoelectronic properties. The computations use the spin‐component‐scaled approximate coupled‐cluster second‐order method (SCS‐CC2), which describes electronic states of predominately neutral excited (NE) and charge transfer (CT) character equally well. Our results show that the characters of the excited states change significantly with the intermolecular orientation and often represent significant mixtures of NE and CT characters. However, PECs and electronic structures of the investigated perylene derivatives are almost independent of the substitution patterns of the perylene core indicating that the observed differences in the optoelectronic properties mainly result from the geometrical structure of the dye aggregate. It also hints at the fact that optical properties can be computed from less‐substituted model compounds if a proper aggregate geometry is chosen. © 2012 Wiley Periodicals, Inc.
First‐principles calculations on thermodynamic properties of BaTiO3rhombohedral phase
Authors: Bandura Andrei V. , Evarestov Robert A. 
Published: April 2012

AbstractThe calculations based on the linear combination of atomic orbitals have been performed for the low‐temperature phase of BaTiO3crystal. Structural and electronic properties, as well as phonon frequencies were obtained using hybrid PBE0 exchange–correlation functional. The calculated frequencies and total energies at different volumes have been used to determine the equation of state and thermal contribution to the Helmholtz free energy within the quasiharmonic approximation. For the first time, the bulk modulus, volume thermal expansion coefficient, heat capacity, and Grüneisen parameters in BaTiO3rhombohedral phase have been estimated at zero pressure and temperatures form 0 to 200 K, based on the results of first‐principles calculations. Empirical equation has been proposed to reproduce the temperature dependence of the calculated quantities. The agreement between the theoretical and experimental thermodynamic properties was found to be satisfactory. © 2012 Wiley Periodicals, Inc.
Simultaneous removal of TOC and TSS in swine wastewater using the partial nitritation process
Authors: De Prá Marina Celant , Kunz Airton , Bortoli Marcelo , Perondi Tiago , Chini Angélica 
Published: April 2012

AbstractBACKGROUND: Considering biological nitrogen removal, the partial nitritation connected with the anaerobic ammonium oxidation (anammox) process is a promising alternative for nitrogen elimination at high loading rates. The objective of the present study was to evaluate the establishment and operation of a partial nitritation process in an airlift reactor with simultaneous removal of total organic carbon and suspended solids using swine wastewater.RESULTS: The partial nitritation reactor was inoculated with a nitrifying sludge at 2.1 gTSS L−1 and fed with an UASB reactor effluent. High organic carbon loading rates, above 2 kgTOC m−3 d−1 have been shown to be potential inhibitors of the partial nitritation process due to competition between autotrophic and heterotrophic bacteria. In this study, the partial nitritation process was established using undiluted swine wastewater, with HRT of 24 h, 1.84 mgO2 L−1 (SD = 0.41) DO, loading rate of 1.14 gTOC L−1 d−1 and 0.91 gN‐NH3 L−1 d−1 for more than 100 consecutive days. At the same time, the system proved to be an effective tool in TOC and TSS removal, reaching 84.9% (SD = 9.3) and 83.1% (SD = 0.1), respectively.CONCLUSION: This result enhances partial nitritation application as a technology for high load nitrogen converting, and allows the possibility of connection with anammox reactors. Copyright © 2012 Society of Chemical Industry
Estimation of the timing of carotid artery flow using peripheral pulse wave‐gated MRI
Authors: Fushimi Yasutaka , Okada Tomohisa , Yamamoto Akira , Kanagaki Mitsunori , Imai Hiroshi , Togashi Kaori 
Published: April 2012

AbstractPurpose:To investigate the relationship between peripheral pulse wave (PPW)‐gating and the carotid systolic pulse wave in a large clinical patient cohort, and to establish a process for correct estimation of delay time from PPW‐gating to foot (ie, beginning) or peak times of carotid systolic pulse waves.Materials and Methods:Subjects comprised 209 patients scanned using 3T magnetic resonance imaging (MRI) for PPW‐gated phase contrast images at the common carotid artery. Stepwise multiple regression analysis was conducted for the relationship between foot or peak times and the following factors after excluding correlated factors with coefficients ≥0.5: pulse rate (PR); systolic blood pressure; diastolic blood pressure; height; body weight; body mass index; Brinkman index; diabetes mellitus; hypertension; and hyperlipidemia.Results:PR showed significant correlation with foot (r = −0.86, P < 0.001) and peak (r = −0.87, P < 0.001) times. The following equations were derived: foot time (msec) = −8.55 × PR + 993.1 and peak time (msec) = −9.21 × PR + 1142.3. No other factors showed significant correlations.Conclusion:PR was the only factor showing significant relationships to foot and peak times of carotid artery flow. The derived equations will facilitate various kinds of noncontrast MR acquisition with simple PPW‐gating. J. Magn. Reson. Imaging 2012;36:454–458. © 2012 Wiley Periodicals, Inc.
Effects of Aspergillus spp. exogenous fibrolytic enzymes on in vitro fermentation of tropical forages
Authors: Facchini Fernanda DA , Reis Victor RA , Roth Anna Paula , Magalhães Karla A , Peixoto‐Nogueira Simone C , Casagrande Daniel R , Reis Ricardo A , Polizeli Maria de Lourdes TM 
Published: April 2012

AbstractBACKGROUND: Cellulose and hemicellulose are quantitatively the most important structural carbohydrates present in ruminant diets. Rumen micro‐organisms produce enzymes that catalyse their hydrolysis, but the complex network formed by structural carbohydrates and lignin reduces their digestibility and restricts efficient utilisation of feeds by ruminants. This study aimed to produce two enzymatic extracts, apply them in ruminant diets to determine the best levels for ruminal digestibility and evaluate their effects on in vitro digestibility.RESULTS: In experiment 1 a two‐stage in vitro technique was used to examine the effects of different enzymatic levels of Aspergillus japonicus and Aspergillus terricola on tropical forages. Enzyme addition had minor effects on corn silage at the highest enzymatic level. In experiment 2 an in vitro gas production (GP) technique was applied to determine apparent in vitro organic matter digestibility and metabolisable energy. The addition of enzymes in GP showed interesting results. Good data were obtained using sugar cane and Tifton‐85 hay supplemented with extracts of A. japonicus and A. terricola respectively.CONCLUSION: Overall, the study suggests that addition of crude extracts containing exogenous fibrolytic enzymes to ruminant diets enhances the effective utilisation of ruminant feedstuffs such as forages. Copyright © 2012 Society of Chemical Industry
Development of an on‐line molecularly imprinted chemiluminescence sensor for determination of trace olaquindox in chick feeds
Authors: Xu Zhixiang , Song Jiaming , Li Liqing , Qiao Xuguang , Chen Haihua 
Published: April 2012

AbstractBACKGROUND: Olaquindox, as one of the antimicrobial growth accelerants, is usually used in livestock production to improve feed efficiency. Due to health concerns over possible carcinogenic, mutagenic and photoallergenic effects of olaquindox on animals, the development of simple, rapid and sensitive analytical method for determination of olaquindox is crucial and necessary.RESULTS: In this study, a surface molecularly imprinted polymer was prepared by a molecular imprinting technique in combination with a sol‐gel process using activated silica gel as a support material. This imprinted material exhibited with good recognition and selective ability, and fast adsorption‐desorption dynamics toward olaquindox. Using it as the recognition element, a new on‐line molecularly imprinted solid phase extraction coupled with chemiluminescence sensor for the determination of olaquindox was developed. The factors affecting preconcentration of the analytes and sensitivity of the method were all investigated. Under the optimal condition, the linear range of the calibration graph was between 2 × 10−8 and 1 × 10−6 g mL−1, and the detection limit of this method was 7 × 10−9 g mL−1. The blank chick feed samples spiked with olaquindox at 0.3, 0.9 and 1.5 µg g−1 levels were extracted and determined by this presented method with recoveries ranging from 87% to 94%. This method was validated by high‐performance liquid chromatography and the results correlated well with those obtained by both methods. Moreover, this method was quantitatively analysed with two contaminated chick feed samples.CONCLUSION: This study will provide a sensitive and fast method for the monitoring of olaquindox residues in foods. Copyright © 2012 Society of Chemical Industry
Physically Crosslinked Nanocomposites from Silicate‐Crosslinked PEO: Mechanical Properties and Osteogenic Differentiation of Human Mesenchymal Stem Cells
Authors: Gaharwar Akhilesh K. , Kishore Vipuil , Rivera Christian , Bullock Whitney , Wu Chia‐Jung , Akkus Ozan , Schmidt Gudrun 
Published: April 2012

AbstractThe mechanical and biological properties of silicate‐crosslinked PEO nanocomposites are studied. A strong correlation is observed between silicate concentration and mechanical properties. In vitro cell culture studies reveal that an increase in silicate concentration enhances the attachment and proliferation of human mesenchymal stem cells significantly. An upregulation in the expression of osteocalcin on nanocomposites compared to the tissue culture polystyrene control is observed. Together, these results suggest that silicate‐based nanocomposites are bioactive and have the potential to be used in a range of biotechnological and biomedical applications such as injectable matrices, biomedical coatings, drug delivery, and regenerative medicine. magnified image
Structure–Property Relationships of Water‐Soluble Ammonium–Ionene Copolymers
Authors: Tamami Mana , Salas‐de la Cruz David , Winey Karen I. , Long Timothy E. 
Published: April 2012

AbstractWater‐soluble random copolymer ammonium ionenes with $\overline{M}_{\rm w}$ in the range of 17.4 to 20.8 kg mol−1 and various charge densities are synthesized from 1,12‐dibromododecane, N,N,N′,N′‐tetramethyl‐1,6‐hexanediamine, and 1,12‐bis(N,N‐dimethylamino)dodecane. Anion exchange of the bromine counterion forms ionenes with TFSI, TFO, and BF4 anions. The nature of the counteranion and charge density tailor the thermal and rheological properties of 12,6/12‐ionenes, respectively. X‐ray scattering reveals microphase separation with a correlation length of ≈7 nm for ionenes with 50 to 90% N,N,N′,N′‐tetramethyl‐1,6‐hexanediamine content. Ionene copolymers display polyelectrolyte behavior in methanol based on a predicted scaling relationship between specific viscosity (ηsp) and concentration.
Effect of Carbon Black Deactivation on the Mechanical and Electrical Properties of Elastomers
Authors: Geberth Eszter , Klüppel Manfred 
Published: April 2012

AbstractThe role of polymer/filler interactions on the mechanical and electrical properties of elastomer nanocomposites is analyzed using dielectric spectroscopy, cyclic stress/strain tests, and online dc‐conductivity measurements. Pristine and deactivated (graphitized) CBs are studied in different rubber matrices. Due to confinement effects, an interphase of strongly immobilized polymer is present between adjacent filler particles, representing stiff but flexible mechanical bonds of the filler network. Under deformation of the sample, these bonds bend and finally break. Cyclic stress/strain measurements are analyzed by fitting the data to a microstructure‐based material model that allows for the evaluation of microscopic parameters of the polymer and filler network. magnified image
Abnormal response to cortical activation in early stages of Huntington disease
Authors: Mochel Fanny , N'Guyen Tra‐My , Deelchand Dinesh , Rinaldi Daisy , Valabregue Romain , Wary Claire , Carlier Pierre G. , Durr Alexandra , Henry Pierre‐Gilles 
Published: April 2012

AbstractBackground:We wished to identify noninvasive in vivo biomarkers of brain energy deficit in Huntington disease.Methods:We studied 15 early affected patients (mean motor United Huntington Disease Rating Scale, 18 ± 9) and 15 age‐ and sex‐matched controls. We coupled 31phosphorus nuclear magnetic resonance spectroscopy with activation of the occipital cortex in order to measure the relative concentrations of adenosine triphosphate, phosphocreatine, and inorganic phosphate before, during, and after visual stimulation.Results:In controls, we observed an 11% increase in the inorganic phosphate/phosphocreatine ratio (P = .024) and a 13% increase in the inorganic phosphate/adenosine triphosphate ratio (P = .016) during brain activation, reflecting increased adenosine diphosphate concentrations. Subsequently, controls had a return to baseline levels during recovery (P = .012 and .022, respectively). In contrast, both ratios were unchanged in patients during and after visual stimulation.Conclusions:31Phosphorus nuclear magnetic resonance spectroscopy could provide functional biomarkers of brain energy deficit to monitor therapeutic efficacy in Huntington disease. © 2012 Movement Disorder Society
Thermal Polymerization of Styrene, Part 1 – Bulk Polymerization
Authors: Katzer Johannes , Pauer Werner , Moritz Hans‐Ulrich 
Published: April 2012

AbstractThe thermal bulk polymerization of styrene is critically reviewed. There is still no generally accepted kinetic model for the thermal radical formation process, but ideal second‐ or third‐order models are widely used for modeling bulk systems. Since initiation and chain transfer reactions cannot be treated independently from one another as long as the same species is considered to be involved, it is concluded that non‐ideal kinetics, possibly in form of a (micro‐)viscosity dependency of the Mayo mechanism, are likely to be present. A mathematical model is presented that keeps the predictive capabilities of the Hui‐Hamielec model, but allows facile implementation of reaction specific modifications. Part 2 of this paper will focus on the effect of compartmentalization on the thermal polymerization of styrene. magnified image
A high‐order accurate particle‐in‐cell method
Authors: Edwards Essex , Bridson Robert 
Published: April 2012

SUMMARYWe propose the use of high‐order weighted essentially non‐oscillatory interpolation and moving‐least‐squares approximation schemes alongside high‐order time integration to enable high‐order accurate particle‐in‐cell methods. The key insight is to view the unstructured set of particles as the underlying representation of the continuous fields; the grid used to evaluate integro–differential coupling terms is purely auxiliary. We also include a novel regularization term to avoid the accumulation of noise in the particle samples without harming the convergence rate. We include numerical examples for several model problems: advection–diffusion, shallow water, and incompressible Navier–Stokes in vorticity formulation. The implementation demonstrates fourth‐order convergence, shows very low numerical dissipation, and is competitive with high‐order Eulerian schemes. Copyright © 2012 John Wiley & Sons, Ltd.
Ultrasound estimated fetal weight slightly below the median is associated with increased risk of spontaneous preterm birth
Authors: Severi Filiberto M. , Bocchi Caterina , Imperatore Alberto , Boni Carlotta , Ferrata Chiara , Florio Pasquale , Reis Fernando M. , Petraglia Felice 
Published: April 2012

ABSTRACTBackgroundThis study investigates the possible relationship between ultrasound estimated fetal weight (EFW) at third trimester and the risk of preterm birth following spontaneous preterm labor in otherwise uncomplicated pregnancies.MethodsWe performed a nested case–control study including 281 cases of spontaneous preterm labor with preterm delivery in the third trimester and 3372 matched controls within a cohort of 6207 consecutive pregnant women. Pregnancies with fetal growth restriction (birth weight <10th centile of population‐based normograms) or fetal anomalies were not included. EFW was calculated by using Hadlock′s formula and converted to fetal gender adjusted multiples of median (MoM) for each gestational age.ResultsEFW correlated with birth weight (r = 0.959, p < 0.0001) and was lower in preterm than in control fetuses (p < 0.0001). The odds ratios (95% confidence intervals) for preterm birth for fetuses below 0.9 MoM, 0.85 MoM, 0.80 MoM, and 0.75 MoM of EFW were, respectively, 4.6 (3.6–5.9), 5.7 (4.3–7.5), 8.5 (5.9–12.1), and 11.2 (6.8–18.3). The independent relationship between preterm birth and lower EFW was confirmed in multivariate analysis with adjustment for potential confounders, such as maternal age, parity, and fetal gender.ConclusionIn asymptomatic women between 28 and 36 weeks of gestation, an EFW lower than 0.90 MoM increases by 4.6 times the risk of spontaneous preterm birth, and the risk increases proportionally to the degree of weight reduction. © 2012 John Wiley & Sons, Ltd.
Preparation of polyacrylonitrile/graphene oxide by in situ polymerization
Authors: Wu Fangfang , Lu Yonggen , Shao Guilin , Zeng Fanlong , Wu Qilin 
Published: April 2012

AbstractHighly oriented molecular structure is essential for high‐performance carbon fibers. The addition of a small amount of graphene sheets may enhance the degree of molecular orientation of precursor fibers during spinning and stabilization by limiting the disorientation of the chain segments. Graphene sheets merge into the carbon fiber structure during carbonization. The structure and properties of polyacrylonitrile containing graphene oxide (GO) prepared by in situ polymerization were investigated. With increasing GO loading, the molecular weight of the polymer decreased gradually from 69 000 g mol−1 for the sample without GO to 60 600 g mol−1 for the sample with 2.5 wt% loading of GO. Scanning electron microscopy and X‐ray diffraction results indicated that GO was dispersed in single layers in the polymer matrix. The degree of crystallization of the polymer with 0.5 wt% GO was increased by 8%. Moreover, differential scanning calorimetry and thermogravimetric analysis showed that an appropriate amount of GO, e.g. 0.5 wt%, made the carbon yield of the polymer increase by 5.0 wt%, because the GO in the composite improved the intermolecular crosslinking reaction. Copyright © 2012 Society of Chemical Industry
Superior reinforcement in polyamide 1010/multiwalled carbon nanotube composites realized by high‐rate drawing and incorporation of compatibilizer
Authors: Mai Fang , Zhou Chengjuan , Yao Meijun , Deng Hua , Fu Qiang 
Published: April 2012

AbstractTo realize the full potential of carbon nanotubes (CNTs) in polymer/CNT nanocomposites, many complicated chemical treatments have been developed to modify the CNTs. Nevertheless, the reinforcing efficiency is still not satisfactory in most cases. In this study, a dramatically improved mechanical enhancement is obtained for polyamide 1010/multiwalled carbon nanotube (MWNT) composites simply by exerting high‐rate drawing and incorporating a commercially available compatibilizer. For the fibers prepared at high draw ratio, their tensile strength and modulus are improved by 137 and 132%, respectively, through adding only 0.5 wt% MWNTs. In particular, the increase in strength is at a very high level for the case of non‐covalent interaction since CNTs could be stretched to failure according to theoretical calculation. It is demonstrated that this reinforcement is mainly attributed to the compatibilizer inducing good dispersion, and the high‐rate drawing inducing strong interfacial interaction and orientation of MWNTs. Copyright © 2012 Society of Chemical Industry