Search results for "STAR"
showing 10 items of 4285 documents
Investor protection and business creation
2003
We study the effects of investor protection on the availability of external finance, entrepreneurship, and creation of new firms in an equilibrium search model of private capital markets. In addition to search frictions, we examine contract frictions, specifically interim and ex post moral hazard problems stemming from entrepreneurs’ possibilities to expropriate financiers. In our model, the government chooses the level of investor protection that determines the transferability of match surplus between entrepreneurs and financiers. The results indicate that anything that increases (decreases) entrepreneurship also increases (decreases) the creation of start-ups. The effect of investor prote…
Dynamical Stark Effect in the nu(2)/nu(4) Vibrational Polyad of SiH(4): Theory and Observation.
2000
We report a theoretical and experimental investigation of the dynamical Stark effect in a tetrahedral molecule, silane (SiH(4)). We use a tetrahedral formalism and Floquet theory to calculate the absorption spectra for the molecule dressed by an intense nonresonant pulsed laser. Experimentally, the dynamical Stark effect is observed for transitions of the nu(2)/nu(4) vibrational polyad of SiH(4) by means of nanosecond diode laser absorption spectroscopy and a Nd:YAG laser excitation. Copyright 2000 Academic Press.
Monitoring Electron-Photon Dressing in WSe 2
2016
Optical pumping of solids creates a non-equilibrium electronic structure where electrons and photons combine to form quasiparticles of dressed electronic states. The resulting shift of electronic levels is known as the optical Stark effect, visible as a red shift in the optical spectrum. Here we show that in a pump-probe setup we can uniquely define a non-equilibrium quasiparticle bandstructure that can be directly measurable with photoelectron spectroscopy. The dynamical photon-dressing (and undressing) of the many-body electronic states can be monitored by pump-probe time and angular resolved photoelectron spectroscopy (tr-ARPES) as the photon-dressed bandstructure evolves in time dependi…
Two-laser multiphoton adiabatic passage in the frame of the Floquet theory. Applications to (1+1) and (2+1) STIRAP
1998
We develop an adiabatic two-mode Floquet theory to analyse multiphoton coherent population transfer in N-level systems by two delayed laser pulses, which is a generalization of the three-state stimulated Raman adiabatic passage (STIRAP). The main point is that, under conditions of non-crossing and adiabaticity, the outcome and feasibility of a STIRAP process can be determined by the analysis of two features: (i) the lifting of degeneracy of dressed states at the beginning and at the end of the laser pulses, and (ii) the connectivity of these degeneracy-lifted branches in the quasienergy diagram. Both features can be determined by stationnary perturbation theory in the Floquet representation…
Rat hepatocytes in primary culture synthesize and secrete cellular fibronectin
1992
Fibronectins, involved in cell-matrix interactions and cell attachment, are glycoproteins which show a remarkable heterogeneity, due to alternative splicing. The type III-related domains, ED-A and ED-B, are present in cellular fibronectin in a variety of ratios whereas they are absent in circulating plasma fibronectin. Fibronectin synthesis by hepatocytes which are accepted as suppliers of plasma fibronectin was studied in primary cultures during a 6-day culture period. Using site-specific antibodies we demonstrate that rat hepatocytes are also able to synthesize and secrete fibronectin bearing the ED-A domain from Day 3 on after inoculation. By immunocytological characterization of the hep…
THE USE OF LACTOBACILLUS PENTOSUS 1MO TO SHORTEN THE DEBITTERING PROCESS TIME OF BLACK TABLE OLIVES (CV. ITRANA AND LECCINO): A PILOT-SCALE APPLICATI…
2006
Fifty lactobacilli isolated from black table olive brines were evaluated for their salt tolerance, resistance to oleuropein and verbascoside, and ability to grow in modified filter-sterilized brines. A strain of Lactobacillus pentosus was selected and used as a starter to ferment, in pilot plant, black olives (Itrana and Leccino cv.) in brines modified for pH, carbohydrate, and growth factor concentrations, at 28 degrees C. The temperature-controlled fermentation of Leccino cv. olives resulted in obtaining ready-to-eat, high-quality table olives in a reduced-time process. HPLC analysis of phenolic compounds from fermented olives showed a decrease of oleuropein, a glucoside secoiridoid respo…
An innovative method to produce green table olives based on "pied de cuve" technology
2015
The technology of “pied de cuve” (PdC) is applied in food process only to produce wines with an enriched community of pro-technological yeasts. PdC promotes the growth of the desirable microbial strains in a small volume of grape must acting as a starter inoculums for higher volumes. The aim of the present work was to investigate the use of partially fermented brines, a technology known as PdC, developed with lactic acid bacteria (LAB) on the microbiological, chemical and sensory characteristics of green fermented table olives during two consecutive campaigns. The experimental plan included two trials based on different PdCs: trial A, PdC obtained with Lactobacillus pentosus OM13; trial B, …
Selected lactic acid bacteria as a hurdle to the microbial spoilage of cheese: Application on a traditional raw ewes' milk cheese
2013
To evaluate the efficacy of lactic acid bacteria (LAB) to improve the hygienic safety of a traditional raw milk cheese, the raw ewes’ milk protected denomination of origin (PDO) Pecorino Siciliano cheese was used as a model system. Different Pecorino Siciliano curds and cheeses were used as sources of autochthonous LAB subsequently used as starter and non-starter LAB. These were screened for their acidification capacity and autolysis. Starter LAB showing the best performance were genotypically differentiated and identified: two strains of Lactococcus lactis subsp. lactis were selected. From the nonstarter LAB, Enterococcus faecalis, Lactococcus garvieae and Streptococcus macedonicus strains…
Synthesis of complex organic molecules in soft x-ray irradiated ices
2019
We study the chemical evolution of H2O:CO:NH3 ice mixtures irradiated with soft X-rays, in the range 250-1250 eV. We identify many nitrogen-bearing molecules such as e.g., OCN-, NH4+ , HNCO, CH3CN, HCONH2, and NH2COCONH2. Several infrared features are compatible with glycine or its isomers. During the irradiation, we detected through mass spectroscopy many species desorbing the ice. Such findings support either the infrared identifications and reveal less abundant species with not clear infrared features. Among them, m/z = 57 has been ascribed to methyl isocyanate (CH3NCO), a molecule of prebiotic relevance, recently detected in protostellar environments. During the warm up after the irradi…
D2hTDS-ST Software for Stark Spectrum Simulation of X2Y4 Asymmetric-Top Molecules
2011
Abstract We present the D 2 h TDS-ST ( D 2 h -Top Data System for Stark effect) program suite with the aim to simulate Stark spectra of any IR active rovibrational polyad of X 2 Y 4 ( D 2 h ) asymmetric-top molecules. D 2 h TDS-ST consists in a series of FORTRAN programs called by scripts. For calculation of Stark spectra, we obtained the expressions of the dipole moment and polarizability operators of X 2 Y 4 molecules using a tensorial formalism. For convenience, we integrated the D 2 h TDS-ST programs into the D 2 h TDS package. The D 2 h TDS suite (including the D 2 h TDS-ST programs) is freely available at the URL: http://icb.u-bourgogne.fr/OMR/SMA/SHTDS/D2HTDS.html .