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131.
Ultrastrong coupling is studied in a modulation-doped parabolic potential well coupled to an inductance-capacitance resonant circuit. In this system, in accordance to Kohn's theorem, strong reduction of the energy level separation caused by the electron-electron interaction compensates the depolarization shift. As a result, a very large ratio of 27% of the Rabi frequency to the center resonance frequency as well as a polariton gap of width 2π × 670 GHz are observed, suggesting parabolic quantum wells as the system of choice in order to explore the ultrastrong coupling regime. 相似文献
132.
We propose two primal heuristics for nonconvex mixed-integer nonlinear programs. Both are based on the idea of rounding the
solution of a continuous nonlinear program subject to linear constraints. Each rounding step is accomplished through the solution
of a mixed-integer linear program. Our heuristics use the same algorithmic scheme, but they differ in the choice of the point
to be rounded (which is feasible for nonlinear constraints but possibly fractional) and in the linear constraints. We propose
a feasibility heuristic, that aims at finding an initial feasible solution, and an improvement heuristic, whose purpose is
to search for an improved solution within the neighborhood of a given point. The neighborhood is defined through local branching cuts or box constraints. Computational results show the effectiveness in practice of these simple ideas, implemented within
an open-source solver for nonconvex mixed-integer nonlinear programs. 相似文献
133.
A two-phase velocity-scalar filtered mass density function (TVSFMDF) formulation developed for large eddy simulation (LES) is applied to a temporally developing counter-current mixing layer seeded with water droplets. Closure models for both the dispersed and carrier phases are developed and implemented that are self-consistent with the original TVSFMDF mathematical formulation developed by Carrara and DesJardin. Several simulation cases are conducted to examine the sensitivity of both evaporating and non-evaporating droplet dispersion on various levels of subgrid scale (SGS) modeling approximation – highlighting the importance of variations in composition space in the phase-coupling terms. 相似文献
134.
Let
be a smooth map of a closed n-dimensional manifold (n2) into the plane and let
be an orthogonal projection. We say that f has the standard lifting property, if every embedding
with
is standard in a certain sense. In this paper we give some sufficient conditions for a generic smooth map f to have the standard lifting property when M is a closed surface or an n-dimensional homotopy sphere. 相似文献
135.
Giorgio Colombo Gianluca Ottolina Giacomo Carrea 《Monatshefte für Chemie / Chemical Monthly》2000,131(6):527-547
Summary. In this article we review how molecular modeling techniques can be used to shed some light on the influence of organic solvents
on the molecular characteristics of proteins and enzymes. Molecular dynamic simulations on bovine pancreas trypsin inhibitor,
chymotrypsin, and subtilisin make it possible to get a deeper understanding into how increased intramolecular interactions
improve conformational rigidity, thus explaining the lower reactivity and the higher thermostability of enzymes in non-aqueous
media. The application of thermodynamics-based models allows first qualitative predictions on the selectivity of many reaction
types; however, the application of quantum mechanical/molecular mechanical methods is required for the development of quantitative
models of actual reactivity patterns.
Received November 18, 1999. Accepted (revised) February 8, 2000 相似文献
136.
Massimiliano Boccia Vincenzo Liuzzo Andrea Pucci Piero Narducci Giacomo Ruggeri 《Macromolecular Symposia》2006,235(1):143-151
Summary: Several salicylaldiminate M(II) complexes of Nickel, Copper and Cobalt have been prepared and mixed with ethylene based polymers in order to prepare new composite materials with interesting morphological and optical properties by profiting of the presence of alkyl chains and push-pull substituents connected to the ligand structure. The phase dispersion behaviour of the binary films has been studied by scanning electron microscopy (SEM) and x-ray microanalysis, whereas the optical properties of the composite samples have been evaluated by UV-vis and fluorescence spectroscopy. The results in absorption have been analysed in terms of the anisotropy induced by the mechanical orientation of the polymer matrix and by the role of the metal centre according to the different strength of the complexes transition dipole moment. The luminescence behaviour have been discussed in terms of potential developments aimed at preparing polymeric supported Schiff base ligands for metal ions sensor applications. 相似文献
137.
Monte Carlo methods are the most popular methods for solving problems in kinetic theory [2, 5]. In this short remark we emphasize some of the side effects due to the use of conservative methods over a finite number of statistical samples (particles) in the simulation. The most relevant aspect is that the steady states of the system are compactly supported and thus they cannot be Maxwellian (or any other non compactly supported statistics) unless the number of particles goes to infinity. These aspects are studied numerically with the help of a simple one-dimensional space homogeneous kinetic model. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
138.
Lawan Ly Xiaoqian Cheng Saravana R. K. Murthy Olivia Z. Jones Taisen Zhuang Steven Gitelis Alan T. Blank Aviram Nissan Mohammad Adileh Matthew Colman Michael Keidar Giacomo Basadonna Jerome Canady 《Molecules (Basel, Switzerland)》2022,27(13)
Soft tissue sarcomas (STS) are a rare and highly heterogeneous group of solid tumors, originating from various types of connective tissue. Complete removal of STS by surgery is challenging due to the anatomical location of the tumor, which results in tumor recurrence. Additionally, current polychemotherapeutic regimens are highly toxic with no rational survival benefit. Cold atmospheric plasma (CAP) is a novel technology that has demonstrated immense cancer therapeutic potential. Canady Cold Helios Plasma (CHCP) is a device that sprays CAP along the surgical margins to eradicate residual cancer cells after tumor resection. This preliminary study was conducted in vitro prior to in vivo testing in a humanitarian compassionate use case study and an FDA-approved phase 1 clinical trial (IDE G190165). In this study, the authors evaluate the efficacy of CHCP across multiple STS cell lines. CHCP treatment reduced the viability of four different STS cell lines (i.e., fibrosarcoma, synovial sarcoma, rhabdomyosarcoma, and liposarcoma) in a dose-dependent manner by inhibiting proliferation, disrupting cell cycle, and inducing apoptosis-like cell death. 相似文献
139.
Annalisa Chiavaroli Viviana di Giacomo Barbara De Filippis Amelia Cataldi Claudio Ferrante Letizia Giampietro 《Molecules (Basel, Switzerland)》2022,27(15)
PPARγ agonists are implicated in the regulation of diabetes and metabolic syndrome and have therapeutic potential in brain disorders. PPARγ modulates appetite through its central effects, especially on the hypothalamic arcuate nucleus (ARC). Previous studies demonstrated that the small molecule GL516 is a PPARγ agonist able to reduce oxidative stress and apoptosis with a potential neuroprotective role. Herein, we investigated the effects of GL516, in vitro and ex vivo, on the levels of hypothalamic dopamine (DA) and serotonin (5-HT). The gene expressions of neuropeptide Y, CART, AgRP, and POMC, which play master roles in the neuroendocrine regulation of feeding behavior and energy balance, were also evaluated. HypoE22 cells were treated with H2O2 (300 μM) for 2 h e 30’ and with different concentrations of GL516 (1 nM-100 µM). The cell viability was evaluated after 24 and 48 h of culturing using the MTT test. DA and 5-HT levels in the HypoE22 cell supernatants were analyzed through HPLC; an ex vivo study on isolated hypothalamic specimens challenged with scalar concentrations of GL516 (1–100 µM) and with pioglitazone (10 µM) was carried out. The gene expressions of CART, NPY, AgRP, and POMC were also determined by a quantitative real-time PCR. The results obtained showed that GL516 was able to reduce DA and 5-HT turnover; moreover, it was effective in stimulating NPY and AgRP gene expressions with a concomitant reduction in CART and POMC gene expressions. These results highlight the capability of GL516 to modulate neuropeptide pathways deeply involved in appetite control suggesting an orexigenic effect. These findings emphasize the potential use of GL516 as a promising candidate for therapeutical applications in neurodegenerative diseases associated with the reduction in food intake and stimulation of catabolic pathways. 相似文献
140.