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971.
Given a parabolic cylinder Ω × (0, T), where Ω is a bounded domain of ${\mathbb{R}^N}$ , we consider IBV problems involving equations of the type $$b(u)_{t} - \Delta_{p} u = \mu$$ where b is a increasing C 1-function and μ is a diffuse measure. We prove the existence and uniqueness of a renormalized solution for this class of nonlinear parabolic equations. 相似文献
972.
Are structural break models true switching models or long memory processes? The answer to this question remains ambiguous. In recent years, many papers have dealt with this problem. Some studies have shown that, under specific conditions, switching models and long memory processes can easily be confused. In this paper, using several generating models (the mean-plus-noise model, the stochastic permanent break model, the Markov switching model, the threshold autoregressive (TAR) model, the sign model, and the structural change model) and several estimation techniques (the Geweke–Porter–Hudak (GPH) technique, detrended fluctuation analysis (DFA), the exact local Whittle (ELW) method, and wavelet methods) we show that, even if the answer is quite simple in some cases, it can be mitigated in other cases. Using French and American inflation rates, we found that the most appropriate process that takes into account the important features of these series is a model that simultaneously combines changes in regimes and long memory behavior. The main result of this study indicates that estimating a long memory parameter without taking into account the presence of breaks in the data sets may lead to misspecification and hence to overestimating the true parameter. 相似文献
973.
Malaud E Piquer D Merle D Molina L Guerrier L Boschetti E Saussine M Marty-Ané C Albat B Fareh J 《Electrophoresis》2012,33(3):470-482
Atherosclerosis is one of the most important causes of cardiovascular and cerebrovascular events. Although phenotypic differentiation between stable and unstable plaques is currently possible, proteomic analysis of the atherosclerotic plaque could offer a global view of the atherosclerosis pathology. With the objective to highlight the detection of low-abundance proteins, we reduced the dynamic range of proteins by combinatorial peptide ligand library treatment of human carotid artery atherosclerotic plaques. After enrichment step, abundance of major proteins was decreased, revealing different protein profiles as assessed by both SDS-polyacrylamide gel electrophoresis and two-dimensional electrophoresis comparative analyses. Identification of proteins that were contained in a spot allowed finding large differences between noncomplicated and complicated plaques from carotid atherosclerotic lesions. Novel low-abundance proteins were detected correlating very well with biological alterations related to atherosclerosis (heat shock protein 27 (HSP27) isoforms, aldehyde dehydrogenase, moesin, Protein kinase C delta-binding protein, and inter-α trypsin inhibitor family heavy chain-related protein (ITIH4)). At the same time, the differential expression of known proteins of interest such as hemoglobin β-chain and heat shock protein 27 between noncomplicated and hemorrhagic complicated plaques was maintained after enrichment step. The detection of different isoforms of a low-abundance protein such as heat shock protein 27 species was actually improved after enrichment of tissue protein extracts. All of these findings clearly support further investigations in view to confirm the role of these proteins as possible biomarkers. 相似文献
974.
Taban-Çalışkan G Mesquita Fernandes D Daran JC Agustin D Demirhan F Poli R 《Inorganic chemistry》2012,51(10):5931-5940
The reaction between the oxometallic complexes Cp*(2)M(2)O(5) and Na(2)M'O(4) (M, M' = Mo, W) in a 1:10 molar ratio in an acidic aqueous medium constitutes a mild and selective entry into the anionic Lindqvist-type hexametallic organometallic mixed oxides [Cp*Mo(x)W(6-x)O(18)](-) [x = 6 (1), 5 (2), 1 (3), 0 (4)]. All of these compounds have been isolated as salts of nBu(4)N(+) (a), nBu(4)P(+) (b), and Ph(4)P(+) (c) cations and two of them (1 and 3) also with the n-butylpyridinium (nBuPyr(+), d) cation. The compounds have been characterized by elemental analyses, thermogravimetric analyses, electrospray mass spectrometry, and IR spectroscopy. The molecular identity and geometry of compounds 1c, 2a, and 2c have been confirmed by single-crystal X-ray diffraction. Density functional theory calculations on models obtained by replacing Cp* with Cp (I-IV) have provided information on the assignment of the terminal M═O and bridging M-O-M vibrations. 相似文献
975.
Méndez M Cesteros Y Marsal LF Giguère A Drouin D Salagre P Formentín P Pallarès J Aguiló M Díaz F Carvajal JJ 《Inorganic chemistry》2012,51(11):6139-6146
Europium-doped lanthanum oxide (5 mol % Eu(3+):La(2)O(3)) was prepared by calcining europium-doped lanthanum hydroxide (5 mol % Eu(3+):La(OH)(3)) previously synthesized by a simple hydrothermal method. Interestingly, we observed different emission Eu(3+) signatures depending on the phase of the host (lanthanum oxide or hydroxide) by cathodoluminescence. Taking into account that lanthanum oxide easily rehydroxylates in air, for the first time, we report the use of cathodoluminiscence as a novel characterization technique to follow the lanthanum oxide rehydroxylation reaction versus time according to different annealing procedures. Additionally, differential thermal-thermogravimetric analysis, infrared spectroscopy, and X-ray diffraction techniques were used to identify the phases formed from the Eu(3+):La(OH)(3) depending on temperature and to study the evolution of La(2)O(3) to La(OH)(3) versus time. The results showed that the higher the temperature and the longer the annealing time, the higher the resistance to rehydroxylation of the Eu(3+):La(2)O(3) sample. 相似文献
976.
Colombo A Locatelli D Roberto D Tessore F Ugo R Cavazzini M Quici S De Angelis F Fantacci S Ledoux-Rak I Tancrez N Zyss J 《Dalton transactions (Cambridge, England : 2003)》2012,41(22):6707-6714
The dipolar and octupolar contributions of the second order nonlinear optical properties of [(4'-(C(6)H(4)-p-D)-2,2':6',2'-terpyridine)-Ru-(4'-(C(6)H(4)-p-A)-2,2':6',2'-terpyridine)]Y(2) heteroleptic complexes (D and A are donor and acceptor groups, respectively), and related free terpyridines and homoleptic complexes, have been obtained by means of a comprehensive combination of Electric Field Induced Second Harmonic generation, Third Harmonic Generation, and Harmonic Light Scattering measurements. These results evidence how a metal can act as a bridge between two π-delocalized terpyridine moieties bearing a D and an A group, respectively, leading to a large quadratic hyperpolarizability hugely dominated by the octupolar contribution. 相似文献
977.
Andriy Fedorov Reinhard Beichel Jayashree Kalpathy-Cramer Julien Finet Jean-Christophe Fillion-Robin Sonia Pujol Christian Bauer Dominique Jennings Fiona Fennessy Milan Sonka John Buatti Stephen Aylward James V. Miller Steve Pieper Ron Kikinis 《Magnetic resonance imaging》2012
Quantitative analysis has tremendous but mostly unrealized potential in healthcare to support objective and accurate interpretation of the clinical imaging. In 2008, the National Cancer Institute began building the Quantitative Imaging Network (QIN) initiative with the goal of advancing quantitative imaging in the context of personalized therapy and evaluation of treatment response. Computerized analysis is an important component contributing to reproducibility and efficiency of the quantitative imaging techniques. The success of quantitative imaging is contingent on robust analysis methods and software tools to bring these methods from bench to bedside. 相似文献
978.
The aim of our study was to validate a Pediatric Voice Symptom Questionnaire (PVSQ) presenting with a parallel form for children and their parents. The items of the questionnaire were elaborated from the results of structured interviews with dysphonic children (DP) and normophonic children (NP) and their mothers and were tested for feasibility in a pilot study involving 42 normophonic children aged 5-13 years. The items were then administered in a test-retest mode to 333 children and their parents (154 boys and 179 girls with a mean age of 9 years, standard deviation: 1.8); 45 consulting DP, 34 nonconsulting dysphonics (NcDP), 163 NP, and 91 others. Classical statistical analyses and an item response modeling approach were used to analyze the results. High internal consistency and good test-retest stability were found. Significant differences between total score of the NP, DP, and NcDP groups were observed both in the children and the parents and also between parental and child score for the NP and NcDP groups (P<0.001-P=0.014). Correlations between child and parental scores were found only in the DP groups (r=0.478; P<0.001). Based on our results, the PVSQ is a valid and reliable instrument for the autoevaluation of dysphonia in the child population. 相似文献
979.
Sedimentation equilibria of ferrofluids: I. Analytical centrifugation in ultrathin glass capillaries
Analytical centrifugation is used for the first time to measure sedimentation equilibrium concentration profiles of a ferrofluid, a concentrated colloidal dispersion of strongly absorbing magnetic nanoparticles. To keep the optical absorbance from becoming too strong, the optical path length is restricted to 50 μm by placing the dispersion in a flat glass capillary. The concentration profile is kept from becoming too steep, despite the relatively high buoyant mass of the nanoparticles, by making novel use of a low-velocity analytical centrifuge that was not designed to measure equilibrium profiles. The experimental approach is validated by comparison with profiles obtained using an analytical ultracentrifuge. At concentrations of a few hundred grams per liter, the osmotic pressures calculated from the equilibrium profiles are lower than expected for hard spheres or non-interacting particles, due to magnetic dipolar interactions. By following the presented experimental approach, it will now also be possible to characterize the interparticle interactions of other strongly absorbing colloidal particles not studied before by analytical centrifugation. 相似文献
980.
Cottineau T Albrecht A Janowska I Macher N Bégin D Ledoux MJ Pronkin S Savinova E Keller N Keller V Pham-Huu C 《Chemical communications (Cambridge, England)》2012,48(9):1224-1226
Novel transparent 1D-TiO(2)/few-layer graphene electrodes are realised by the anodic growth of vertically aligned TiO(2) nano-tubes on a few-layer graphene film coated on a glass substrate. 相似文献