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排序方式: 共有441条查询结果,搜索用时 15 毫秒
431.
Tommaso Benincasa Angelo Favini Costică Moroşanu 《Journal of Optimization Theory and Applications》2011,148(1):31-45
In this paper we prove the convergence of an iterative scheme of fractional steps type for a non-homogeneous Cauchy-Neumann
boundary optimal control problem governed by non-linear phase-field system, when the boundary control is dependent both on
time and spatial variables. Moreover, necessary optimality conditions are established for the approximating process. The advantage
of such approach leads to a numerical algorithm in order to approximate the original optimal control problem. 相似文献
432.
Several strong convergence results involving two distinct four parameter proximal point algorithms are proved under different sets of assumptions on these parameters and the general condition that the error sequence converges to zero in norm. Thus our results address the two important problems related to the proximal point algorithm — one being that of strong convergence (instead of weak convergence) and the other one being that of acceptable errors. One of the algorithms discussed was introduced by Yao and Noor (2008) [7] while the other one is new and it is a generalization of the regularization method initiated by Lehdili and Moudafi (1996) [9] and later developed by Xu (2006) [8]. The new algorithm is also ideal for estimating the convergence rate of a sequence that approximates minimum values of certain functionals. Although these algorithms are distinct, it turns out that for a particular case, they are equivalent. The results of this paper extend and generalize several existing ones in the literature. 相似文献
433.
Cywinski PJ Moro AJ Ritschel T Hildebrandt N Löhmannsröben HG 《Analytical and bioanalytical chemistry》2011,399(3):1215-1222
Novel fluorescent nanosensors, based on a naphthyridine receptor, have been developed for the detection of guanosine nucleotides,
and both their sensitivity and selectivity to various nucleotides were evaluated. The nanosensors were constructed from polystyrene
nanoparticles functionalized by (N-(7-((3-aminophenyl)ethynyl)-1,8-naphthyridin-2-yl)acetamide) via carbodiimide ester activation. We show that this naphthyridine
nanosensor binds guanosine nucleotides preferentially over adenine, cytosine, and thymidine nucleotides. Upon interaction
with nucleotides, the fluorescence of the nanosensor is gradually quenched yielding Stern–Volmer constants in the range of
2.1 to 35.9 mM−1. For all the studied quenchers, limits of detection (LOD) and tolerance levels for the nanosensors were also determined.
The lowest (3σ) LOD was found for guanosine 3’,5’-cyclic monophosphate (cGMP) and it was as low as 150 ng/ml. In addition,
we demonstrated that the spatial arrangement of bound analytes on the nanosensors’ surfaces is what is responsible for their
selectivity to different guanosine nucleotides. We found a correlation between the changes of the fluorescence signal and
the number of phosphate groups of a nucleotide. Results of molecular modeling and ζ-potential measurements confirm that the
arrangement of analytes on the surface provides for the selectivity of the nanosensors. These fluorescent nanosensors have
the potential to be applied in multi-analyte, array-based detection platforms, as well as in multiplexed microfluidic systems. 相似文献
434.
Lepore L Gualtieri MJ Malafronte N Cotugno R Dal Piaz F Ambrosio L De Falco S De Tommasi N 《Natural product communications》2011,6(7):943-946
Angiogenesis is a crucial step in many pathological conditions like cancer, inflammation and metastasis formation; on these basis the search for antiangiogenic agents has widened. In order to identify new compounds able to interfere in the Vascular Endothelial Growth Factor Receptor-1 (VEGFR-1, also known as Flt-1) recognition by VEGFs family members, we screened Calycolpus moritzianus (O. Berg) Burret leaves extracts by a competitive ELISA-based assay. MeOH and CHCl3 extracts and several their fractions demonstrated to be able to prevent VEGF or PlGF interaction with Flt-1, with an inhibition about 50% at concentration of 100 microg/mL. Phytochemical and pharmacological investigation of the active fractions led to the isolation of flavonoids, and terpenes. 相似文献
435.
A. Di Nitto E. Vardaci A. Brondi G. La Rana R. Moro P. N. Nadtochy M. Trotta A. Ordine A. Boiano M. Cinausero E. Fioretto G. Prete V. Rizzi D. V. Shetty M. Barbui D. Fabris M. Lunardon G. Montagnoli S. Moretto G. Viesti N. Gelli F. Lucarelli G. N. Knyazheva E. M. Kozulin 《The European Physical Journal A - Hadrons and Nuclei》2011,47(6):1-14
Light charged particle (LCP) emission in the evaporation residue (ER) and fusion fission (FF) channels have been studied for the 200 MeV 32S + 100Mo reaction, leading to 132Ce composite nuclei at E x =122 MeV. The main goal was to study the decay of 132 Ce on the basis of an extended set of observables, to get insights on the fission dynamics. The proton and alpha particle energy spectra, their multiplicities, ER-LCP angular correlations, ER and FF angular distributions, and ER and FF cross-sections were measured. The measured observables were compared with the Statistical Model (SM). Using standard parameters, the model was able to reproduce only the pre-scission multiplicities and the FF and ER cross-sections. The calculation was observed to strongly overestimate the proton and alpha particle multiplicities in the ER channel. Disagreements were also observed for the ER-LCP correlations, the LCP energy spectra and the ER angular distribution. By varying the SM input parameters over a wide range of values, it is shown that it is not possible to reproduce all the observables simultaneously with a unique set of parameters. The inadequacy of the model in reproducing the ER particle multiplicities is also observed analysing data from the literature for other systems in the A ≈ 150 and E x ≈ 100?200 MeV region. These results indicate serious limitations about the use of the SM in extracting information on fission dynamics. 相似文献
436.
437.
Emanuele F. Pissinati José A. C. Delgado Pedro A. M. Moro Dr. José T. M. Correia Prof. Dr. Roberto G. S. Berlinck Prof. Dr. Márcio W. Paixão 《European journal of organic chemistry》2023,26(21):e202300274
A site-selective carbamoylation strategy to access non-proteinogenic N4-modified asparagines has been described. The protocol is characterized by mild reaction conditions, high functional group compatibility, and a wide diversity of functionalized carbamoyl radicals making possible the access to peptides, pharmaceuticals, and natural N4-asparagine conjugates, as well as enantioenriched unnatural N4-asparagines. Besides that, deuterated analogues were achieved with the insertion of D2O and enantioenriched derivatives could be obtained in 15 min in continuous-flow conditions. 相似文献
438.
Dr. Giulia Moro Dr. Chiara Dalle Fratte Prof. Dr. Nicola Normanno Prof. Dr. Federico Polo Prof. Dr. Stefano Cinti 《Angewandte Chemie (International ed. in English)》2023,62(51):e202309135
Point-of-care (PoC) testing is revolutionizing the healthcare sector improving patient care in daily hospital practice and allowing reaching even remote geographical areas. In the frame of cancer management, the design and validation of PoC enabling the non-invasive, rapid detection of cancer markers is urgently required to implement liquid biopsy in clinical practice. Therefore, focusing on stable blood-based markers with high-specificity, such as microRNAs, is of crucial importance. In this work, we highlight the potential impact of circulating microRNAs detection on cancer management and the crucial role of PoC testing devices, especially for low-income countries. A detailed discussion about the challenges that should be faced to promote the technological transfer and clinical use of these tools has been added, to provide the readers with a complete overview of potentialities and current limitations. 相似文献
439.
Hideyuki Higashimura Kiyoshi Fujisawa Yoshihiko Moro‐oka Shuhei Namekawa Masaaki Kubota Akinobu Shiga Hiroshi Uyama Shiro Kobayashi 《Macromolecular rapid communications》2000,21(16):1121-1124
New heat‐reversibly crystalline poly‐(alkylated phenylene oxide)s are described. the oxidative polymerization of 2,5‐dimethylphenol catalyzed by (1,4,7‐triisopropyl‐1,4,7‐triazacyclononane) copper dichloride produced poly(2,5‐dimethyl‐1,4‐phenylene oxide), which showed heat‐reversible crystallinity with a high melting point at ca. 300°C, although the isomeric polymer, poly(2,6‐dimethyl‐1,4‐phenylene oxide), never recrystallizes once melted. The polymerization of 2,5‐diethylphenol and 2,5‐dipropylphenol gave the polymers consisting of 1,4‐phenylene oxide units; the latter polymer possessed heat‐reversible crystallinity, however, the former one did not. 相似文献
440.