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111.
Scaglia E Sockalingum GD Schmitt J Gobinet C Schneider N Manfait M Thiéfin G 《Analytical and bioanalytical chemistry》2011,401(9):2919-2925
Assessment of liver fibrosis is of paramount importance to guide the therapeutic strategy in patients with chronic hepatitis
C (CHC). In this pilot study, we investigated the potential of serum Fourier transform infrared (FTIR) spectroscopy for differentiating
CHC patients with extensive hepatic fibrosis from those without fibrosis. Twenty-three serum samples from CHC patients were
selected according to the degree of hepatic fibrosis as evaluated by the FibroTest: 12 from patients with no hepatic fibrosis
(F0) and 11 from patients with extensive fibrosis (F3–F4). The FTIR spectra (ten per sample) were acquired in the transmission
mode and data homogeneity was tested by cluster analysis to exclude outliers. After selection of the most discriminant wavelengths
using an ANOVA-based algorithm, the support vector machine (SVM) method was used as a supervised classification model to classify
the spectra into two classes of hepatic fibrosis, F0 and F3–F4. Given the small number of samples, a leave-one-out cross-validation
algorithm was used. When SVM was applied to all spectra (n = 230), the sensitivity and specificity of the classifier were 90.1% and 100%, respectively. When SVM was applied to the
subset of 219 spectra, i.e., excluding the outliers, the sensitivity and specificity of the classifier were 95.2% and 100%,
respectively. This pilot study strongly suggests that the serum from CHC patients exhibits infrared spectral characteristics,
allowing patients with extensive fibrosis to be differentiated from those with no hepatic fibrosis. 相似文献
112.
A remarkable influence of the orientation of a polar side chain on the direction of the S(1) ← S(0) transition dipole moment of monosubstituted benzenes was previously reported from high-resolution electronic spectroscopy. In search for a more general understanding of this non-Condon behavior, we investigated ethylamino-substituted indole and benzene (tryptamine and 2-phenylethylamine) using ab initio theory and compared the results to rotationally resolved laser-induced fluorescence measurements. The interaction of the ethylamino side chain with the benzene chromophore can evoke a rotation and a change of ordering of the molecular orbitals involved in the excitation, leading to state mixing and large changes in the orientation of the excited-state transition dipole moment. These changes are much less pronounced in tryptamine with the indole chromophore, where a rotation of the transition dipole moment is attributed to Rydberg contributions of the nitrogen atom of the chromophore. For phenylethylamine, a strong dependence of the oscillator strengths of the lowest two singlet states from the conformation of the side chain is found, which makes the use of experimental vibronic intensities for assessment of relative conformer stabilities at least questionable. 相似文献
113.
Kwan P Schmitt D Volosin AM McIntosh CL Seo DK Jones AK 《Chemical communications (Cambridge, England)》2011,47(45):12367-12369
Stable immobilization of two redox proteins, cytochrome c and azurin, in a thin film of highly mesoporous antimony-doped tin oxide is demonstrated via UV-vis spectroscopic and electrochemical investigation. 相似文献
114.
Gaidzik N Kaiser A Kowalczyk D Westerlind U Gerlitzki B Sinn HP Schmitt E Kunz H 《Angewandte Chemie (International ed. in English)》2011,50(42):9977-9981
A shot in the arm for cancer treatment: Two MUC1 tetanus toxoid vaccines were synthesized and induced a strong immune response in mice. The antibodies elicited by the vaccines show a high selectivity for the tumor cells in mammary carcinoma tissues and also distinguish between tumor tissues at different stages. 相似文献
115.
116.
W. Hanke O. Schmitt H. Endres R. Kleiner P. Müller 《The European Physical Journal B - Condensed Matter and Complex Systems》1998,5(3):465-471
A quantitative analysis of a microscopic model for the intrinsic Josephson effect in high-temperature superconductors based
on interlayer tunneling is presented both within a mean-field BCS evaluation and a numerically essentially exact Quantum Monte-Carlo
study. The pairing correlations in the CuO2-planes are modelled by a 2D Hubbard model with attractive interaction, a model which accounts well for some of the observed
features such as the short planar coherence length. The stack of Hubbard planes is arranged on a torus, which is threaded
by a magnetic flux. The current perpendicular to the planes is calculated as a function of applied flux (i.e. the phase), and - after careful elimination of finite-size effects due to single-particle tunneling - found to display a
sinusoidal field dependence in accordance with interlayer Josephson tunneling. Studies of the temperature dependence of the
supercurrent reveal at best a mild elevation of the Josephson transition temperature compared to the planar Kosterlitz-Thouless
temperature. These and other results on the dependence of the model parameters are compared with a standard BCS evaluation.
Received: 24 February 1998 / Revised: 28 April 1998 / Accepted: 23 June 1998 相似文献
117.
J. Arnold B. van den Brandt M. Daum M. Finger M. Finger Jr. J. Franz N. Goujon-Naef P. Hautle R. Hess A. Janata J.A. Konter H. Lacker C. Lechanoine-Leluc F. Lehar S. Mango D. Rapin E. Rössle R. Schirmaier P.A. Schmelzbach M. Schmidt H. Schmitt P. Sereni M. Slunecka A. Teglia B. Vuaridel 《The European Physical Journal A - Hadrons and Nuclei》1998,2(4):411-415
Abstact: The kinetic energy spectrum and the polarization of the PSI neutron beam produced in the reaction 12C(p,n)X at 0° with 590 MeV polarized protons were investigated. A strong energy dependence of the neutron beam polarization is
observed which was not expected at the time the neutron beam was built.
Received: 3 April 1998 相似文献
118.
119.
Klaus D. A. Wendt Klaus Blaum Christopher Geppert Peter Müller Wilfried Nörtershäuser Annette Schmitt Philipp Schumann Norbert Trautmann Bruce A. Bushaw 《Hyperfine Interactions》2005,162(1-4):147-157
A variety of research activities in the field of fundamental and applied nuclear physics has evolved in the last years using
resonantly tuned radiation from powerful lasers. The technique of resonance ionization spectroscopy has delivered outstanding
results and found broad acceptance in the last years as a particularly efficient and highly selective method for rare and
exotic radioisotope studies. It is used for production, spectroscopy and detection of these species and provides complete
isobaric, high isotopic and even some isomeric selection, which altogether is needed for on-line investigation of short lived
species far off stability as well as for ultra trace determination. Good overall efficiency pushes the experimental limits
of detection in elemental trace analysis down to below 106 atoms per sample, and additionally isotopic selectivity as high as 3 × 1012 has been demonstrated. The widespread potential of resonance ionization techniques is discussed, focusing on the experimental
arrangements for applications in selective on-line isotope production, spectroscopy of rare radioisotopes and ultra trace
determination of radiotoxic isotopes like 238Pu to 244Pu, 135,137Cs, 89,90Sr or 41Ca in environmental, technical and biomedical samples. 相似文献
120.