排序方式: 共有25条查询结果,搜索用时 31 毫秒
1.
Two different relaxed problems associated with a problem of optimal control theory, governed by an ODE, are considered: the first is obtained by Young's methods and the second by semicontinuity arguments. A formula which relates the two relaxed functionals to each other is given. 相似文献
2.
Salvatore D'Aniello George H Fisher Enza Topo Gabriele Ferrandino Jordi Garcia-Fernàndez Antimo D'Aniello 《BMC neuroscience》2007,8(1):109
Background
NMDA (N-methyl-D-aspartic acid) is a widely known agonist for a class of glutamate receptors, the NMDA type. Synthetic NMDA elicits very strong activity for the induction of hypothalamic factors and hypophyseal hormones in mammals. Moreover, endogenous NMDA has been found in rat, where it has a role in the induction of GnRH (Gonadotropin Releasing Hormone) in the hypothalamus, and of LH (Luteinizing Hormone) and PRL (Prolactin) in the pituitary gland. 相似文献3.
New stable [6,6]-methano cycloadducts and fulleropyrazolines containing electron-withdrawing groups have been obtained by the reaction of ethyl diazopyruvate with [60]fullerene. The results obtained by a systematic study conducted both in thermal and catalytic conditions have provided crucial indications concerning the mechanism of this important cluster opening process in fullerene chemistry. 相似文献
4.
Paulovich FV Maki RM de Oliveira MC Colhone MC Santos FR Migliaccio V Ciancaglini P Perez KR Stabeli RG Perinoto AC Oliveira ON Zucolotto V 《Analytical and bioanalytical chemistry》2011,400(4):1153-1159
Recent advances in the control of molecular engineering architectures have allowed unprecedented ability of molecular recognition in biosensing, with a promising impact for clinical diagnosis and environment control. The availability of large amounts of data from electrical, optical, or electrochemical measurements requires, however, sophisticated data treatment in order to optimize sensing performance. In this study, we show how an information visualization system based on projections, referred to as Projection Explorer (PEx), can be used to achieve high performance for biosensors made with nanostructured films containing immobilized antigens. As a proof of concept, various visualizations were obtained with impedance spectroscopy data from an array of sensors whose electrical response could be specific toward a given antibody (analyte) owing to molecular recognition processes. In addition to discussing the distinct methods for projection and normalization of the data, we demonstrate that an excellent distinction can be made between real samples tested positive for Chagas disease and Leishmaniasis, which could not be achieved with conventional statistical methods. Such high performance probably arose from the possibility of treating the data in the whole frequency range. Through a systematic analysis, it was inferred that Sammon's mapping with standardization to normalize the data gives the best results, where distinction could be made of blood serum samples containing 10(-7) mg/mL of the antibody. The method inherent in PEx and the procedures for analyzing the impedance data are entirely generic and can be extended to optimize any type of sensor or biosensor. 相似文献
5.
Macchiarulo A Gioiello A Thomas C Massarotti A Nuti R Rosatelli E Sabbatini P Schoonjans K Auwerx J Pellicciari R 《Journal of chemical information and modeling》2008,48(9):1792-1801
Bile acids regulate nongenomic actions through the activation of TGR5, a membrane receptor that is G protein-coupled to the induction of adenylate cyclase. In this work, a training set of 43 bile acid derivatives is used to develop a molecular interaction field analysis (MFA) and a 3D-quantitative structure-activity relationship study (3D-QSAR) of TGR5 agonists. The predictive ability of the resulting model is evaluated using an external set of compounds with known TGR5 activity, and six bile acid derivatives whose unknown TGR5 activity is herein assessed with in vitro luciferase assay of cAMP formation. The results show a good predictive model and indicate a statistically relevant degree of correlation between the TGR5 activity and the molecular interaction fields produced by discrete positions of the bile acid scaffold. This information is instrumental to extend on a quantitative basis the current structure-activity relationships of bile acids as TGR5 modulators and will be fruitful to design new potent and selective agonists of the receptor. 相似文献
6.
Natalini B Sardella R Camaioni E Gioiello A Pellicciari R 《Analytical and bioanalytical chemistry》2007,388(8):1681-1688
The discovery that bile acids are involved in the modulation of nuclear steroid receptors has prompted renewed interest in
this field of research. Due to the nature of research in this field, a technique that enables simple and effective assessment
of the hydrophobic/hydrophilic balance, thus improving and speeding up evaluations of the biological profiles of these compounds,
is greatly needed. In this context, both CMC value determination and RP-HPLC mobility evaluation were explored as possible
approaches. While the CMC was calculated using the noninvasive conductimetric method, the RP-HPLC mobility was assessed by
measuring the retention factor at several mobile phase compositions and extrapolating back to the pure aqueous mobile phase.
The correlation of the CMC with the derived chromatographic hydrophobic index ϕ
0 was satisfactory.
Figure Experimental versus predicted pCMC values 相似文献
7.
8.
Gaetano Corso Monica Gelzo Angela Chambery Valeria Severino Antimo Di Maro Filomena Schiano Lomoriello Oceania D'Apolito Antonio Dello Russo Patrizia Gargiulo Ciro Piccioli Paolo Arcari 《Journal of separation science》2012,35(21):2986-2993
Spectroscopic and MS techniques were used to characterize the pigments and the composition of polar and nonpolar binders of a stray wall painting fragment from Liternum (Italy) archaeological excavation. X‐ray fluorescence and diffraction analysis of the decorations indicated mainly the presence of calcite, quartz, hematite, cinnabar, and cuprorivaite. Infrared spectroscopy, GC coupled to flame‐ionization detector, and MS analysis of the polar and nonpolar components extracted from paint layers from three different color regions revealed the presence of free amino acids, sugars, and fatty acids. Interestingly, LC‐MS shotgun analysis of the red painting region showed the presence of αS1‐casein of buffalo origin. Compared to our previous results from Pompeii's wall paintings, even though the Liternum painting mixture contained also binders of animal origin, the data strongly suggest that in both cases a tempera painting technique was utilized. 相似文献
9.
Venturoni F Gioiello A Sardella R Natalini B Pellicciari R 《Organic & biomolecular chemistry》2012,10(20):4109-4115
A multi-gram scale protocol for the N-acyl amidation of bile acids with glycine and taurine has been successfully developed under continuous flow processing conditions. Selecting ursodeoxycholic acid (UDCA) as the model compound and N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline (EEDQ) as the condensing agent, a modular mesoreactor assisted flow set-up was employed to significantly speed up the optimization of the reaction conditions and the flow scale-up synthesis. The results in terms of yield, in line purification, analysis, and implemented flow set-up for the reaction optimization and large scale production are reported and discussed. 相似文献
10.