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121.
Lester C. E. Taylor Robert L. Johnson Roberto Raso 《Journal of the American Society for Mass Spectrometry》1995,6(5):387-393
We report the introduction and use of an atmospheric pressure chemical ionization liquid chromatography-mass spectrometry instrument that has been designed specifically for use by the synthetic chemist on an open access, walk-in basis. This instrument has been configured with an easy-to-use sample log-in terminal that requires the user to provide only a sample identification number and a user name. Sample analysis takes approximately 4 min and provides the synthetic and medicinal chemist with rapid and reliable mass spectrometry analysis. Since installation of the system, it has analyzed an average of about 80 samples per day and has the capacity to run over 100 samples per day without the intervention of a specialist operator. This capability has eliminated the need for an operator to analyze routine samples and allows the mass spectroscopist more time to deal with problem solving. 相似文献
122.
Jessica Gasparello Chiara Papi Matteo Zurlo Laura Gambari Andrea Rozzi Alex Manicardi Roberto Corradini Roberto Gambari Alessia Finotti 《Molecules (Basel, Switzerland)》2022,27(4)
Glioblastoma multiforme (GBM) is a lethal malignant tumor accounting for 42% of the tumors of the central nervous system, the median survival being 15 months. At present, no curative treatment is available for GBM and new drugs and therapeutic protocols are urgently needed. In this context, combined therapy appears to be a very interesting approach. The isothiocyanate sulforaphane (SFN) has been previously shown to induce apoptosis and inhibit the growth and invasion of GBM cells. On the other hand, the microRNA miR-15b is involved in invasiveness and proliferation in GBM and its inhibition is associated with the induction of apoptosis. On the basis of these observations, the objective of the present study was to determine whether a combined treatment using SFN and a peptide nucleic acid interfering with miR-15b-5p (PNA-a15b) might be proposed for increasing the pro-apoptotic effects of the single agents. To verify this hypothesis, we have treated GMB U251 cells with SFN alone, PNA-a15b alone or their combination. The cell viability, apoptosis and combination index were, respectively, analyzed by calcein staining, annexin-V and caspase-3/7 assays, and RT-qPCR for genes involved in apoptosis. The efficacy of the PNA-a15b determined the miR-15b-5p content analyzed by RT-qPCR. The results obtained indicate that SFN and PNA-a15b synergistically act in inducing the apoptosis of U251 cells. Therefore, the PNA-a15b might be proposed in a “combo-therapy” associated with SFN. Overall, this study suggests the feasibility of using combined treatments based on PNAs targeting miRNA involved in GBM and nutraceuticals able to stimulate apoptosis. 相似文献
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125.
Kobra Mahdavipour Mahshid Khazaei Shadfar Hossein Rangani Jahromi Roberto Morandotti Rosario Lo Franco 《Entropy (Basel, Switzerland)》2022,24(3)
A witness of non-Markovianity based on the Hilbert–Schmidt speed (HSS), a special type of quantum statistical speed, has been recently introduced for low-dimensional quantum systems. Such a non-Markovianity witness is particularly useful, being easily computable since no diagonalization of the system density matrix is required. We investigate the sensitivity of this HSS-based witness to detect non-Markovianity in various high-dimensional and multipartite open quantum systems with finite Hilbert spaces. We find that the time behaviors of the HSS-based witness are always in agreement with those of quantum negativity or quantum correlation measure. These results show that the HSS-based witness is a faithful identifier of the memory effects appearing in the quantum evolution of a high-dimensional system with a finite Hilbert space. 相似文献
126.
127.
Julián I. Peña Rosselló Horacio S. Wio Roberto R. Deza Peter Hänggi 《The European Physical Journal B - Condensed Matter and Complex Systems》2017,90(2):34
The performance of a ring of linearly coupled, monostable nonlinear oscillators is optimized towards its goal of acting as energy harvester – through piezoelectric transduction – of mesoscopic fluctuations, which are modeled as Ornstein-Uhlenbeck noises. For a single oscillator, the maximum output voltage and overall efficiency are attained for a soft piecewise-linear potential (providing a weak attractive constant force) but they are still fairly large for a harmonic potential. When several harmonic springs are linearly and bidirectionally coupled to form a ring, it is found that counter-phase coupling can largely improve the performance while in-phase coupling worsens it. Moreover, it turns out that few (two or three) coupled units perform better than more. 相似文献
128.
Roberto Beneduci 《International Journal of Theoretical Physics》2011,50(12):3724-3736
In the present paper, we review some recent results about commutative positive operator valued measures (POVMs) and single
out some open problems. We introduce a conjecture about the extension of some recent results and prove some important consequences
of such conjecture. In particular, we prove that it implies the universal character of some of the mathematical objects we
introduce, i.e., the fact that they do not depend on the POV measure we are considering. We analyze the relevance of this
result. Finally, we point out that some of the results we present admit a constructive proof and we show the relevance of
this fact to the theory of commutative POV measures. 相似文献
129.
Roberto Peirone 《Communications in Mathematical Physics》1999,207(1):67-80
I prove that in (sufficiently small) tubular ρ$-neighborhoods of a given C
3 manifold of codimension 1, any two points can be connected by a billiard trajectory, and that in addition there exists such
a trajectory having at most collision points, for a suitable H>0, provided the manifold is of class C
3.
Received: 19 June 1998 / Accepted: 7 April 1999 相似文献
130.