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151.
152.
Marida Bertocchi Rosella Giacometti Leon Slominski 《Annals of Operations Research》2000,97(1-4):111-129
In this paper we present a model for management of bond portfolio including financing and investment repo contracts. Different
specifications are suggested in order to reduce the problem to a linear programming problem and to consider a self-financing
portfolio. The models are tested on historical data assuming a technical time scale equal to the minimum length of the contracts
in the portfolio. We also compared different operative strategies on a time horizon of one month.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
153.
154.
Rita Traversi Silvia Becagli Emiliano Castellano Ombretta Largiuni Alessio Migliori Mirko Severi 《International journal of environmental analytical chemistry》2013,93(6-7):457-470
The chemical analysis of shallow firn cores sampled in coastal and plateau areas in Northern Victoria Land and along a transect from Talos Dome to Dome C (East Antarctica, Pacific Ocean sector) allowed a global view of spatial and temporal changes in chemical composition of snow depositions over the last 100 years. Variations in concentration of primary (sea spray) and secondary (biogenic emission, atmospheric inputs) source markers were observed and discussed as a function of distance from the sea and altitude. In the stations characterized by relatively high snow accumulation rates, the sub-sampling resolution was sufficient to obtain a stratigraphic dating by using the periodical variations of seasonal markers. In these stations, a subdivision in “summer” and “winter” samples was carried out in order to study the seasonal changes of the contributions of the measured compounds to the snow composition as elevation and distance from the sea increase. Some evidence of post-depositional effects which are able to change the original deposition of chloride and nitrate, was observed at stations with low accumulation rates. The reliability of the depth/concentration profile of these substances for reconstructing past deposition was also discussed. 相似文献
155.
Poppelaars FA Henneman L Adèr HJ Cornel MC Hermens RP van der Wal G ten Kate LP 《Community genetics》2003,6(3):157-165
BACKGROUND: Since the identification of the cystic fibrosis (CF) gene, large-scale CF carrier screening has become possible. One possible target group is couples planning a pregnancy (preconceptional screening), providing a maximum number of reproductive options and a minimum of time constraints. OBJECTIVES: To identify obstacles in the implementation of a preconceptional CF carrier screening programme, to find out how potential providers and the target population think the screening should be implemented, and to determine whether potential providers think they are able to provide the screening programme. METHODS: A survey was conducted among 200 general practitioners (GPs), 134 Municipal Health Service (MHS) workers and 303 recently married couples. RESULTS: 52% (102/197) of the eligible GPs participated, 84% (113/134) of the MHS workers and 70% (380/544) of the individuals planning a pregnancy. In general, potential providers and the target population had a positive attitude towards CF screening. Preferred methods of informing the target population were: in leaflets, during a GP consultation for those people seeking advice before pregnancy, and sending a personal invitation to all people of reproductive age. Potential providers believed that they would be able to provide the screening programme. Important perceived obstacles were the absence of a preconceptional care setting, high workload, and lack of financial resources. CONCLUSION: Different intervention strategies will be necessary to overcome the obstacles in the implementation. The positive attitude towards CF carrier screening in combination with the willingness of the potential providers to participate in the screening programme will make it easier to overcome the obstacles. 相似文献
156.
Silvana E. Vignaduzzo Luciana Vera-Candioti Patricia M. Castellano H��ctor C. Goicoechea Teodoro S. Kaufman 《Chromatographia》2011,74(7-8):609-617
A capillary zone electrophoresis method for the simultaneous determination of pridinol mesylate (PRI) and meloxicam (MEL) employing epinastine hydrochloride and piroxicam as internal standards, was developed and optimized employing experimental design and response surface methodologies. The separation was optimally achieved in less than 2 min at 30 kV in an uncoated fused-silica capillary (41.4 cm × 75 ??m I.D.), employing an 18 mmol L?1 sodium phosphate buffer solution (pH 5.90) at 25 °C. Samples were injected in hydrodynamic mode (50 mbar, 5 s) and the analytes were spectrophotometrically detected at 200 nm. Method robustness was demonstrated by ANOVA of determinations performed under conditions slightly different from the optimum. The method was validated regarding separation selectivity (peak purity factors > 0.99), linearity and range (PRI = 17.6?C31.4 mg L?1; MEL = 66.5?C122.5 mg L?1), accuracy (PRI = 100.2?C101.9%; MEL = 98.9?C100.7%) and precision. The RSD values obtained were ??1.3% for injection repeatability and ??1.9% for intra-day precision. The limits of detection (1.0 and 0.9 mg L?1) and quantification (3.3 and 16.5 mg L?1) of PRI and MEL, respectively, were also determined. The method was successfully applied to the determination of both drugs in three brands of tablet formulations. No statistically significant differences were observed when these results were compared with those of a RP-HPLC method. 相似文献
157.
158.
Dr. Annalisa Mancini Dr. M. Carla Aragoni Dr. Ann L. Bingham Dr. Carlo Castellano Dr. Susanne L. Coles Prof. Francesco Demartin Prof. Michael B. Hursthouse Prof. Francesco Isaia Prof. Vito Lippolis Dr. Giuseppe Maninchedda Dr. Anna Pintus Dr. Massimiliano Arca 《化学:亚洲杂志》2013,8(12):3071-3078
The reactions of 1,3,8,10‐tetrakis(4′‐fluorophenyl)‐4,5,6,7‐tetrathiocino[1,2‐b:3,4‐b′]diimidazolyl‐2,9‐dithione ( 4 ) and molecular diiodine afforded spoke adducts with stoichiometries 4·I2 and 4? 3I2, isolated in the compound 4? 3I2 ? xCH2Cl2 ? (1?x)I2 (x=0.70), and characterized by single‐crystal XRD and FT–Raman spectroscopy. The nature of the reaction products was investigated under the prism of theoretical calculations carried out at the DFT level. The structural data, FT–Raman spectroscopy, and quantum mechanical calculations agree in indicating that the introduction of fluorophenyl substituents results in a lowering of the Lewis basicity of this class of bis(thiocarbonyl) donors compared with alkyl‐substituted tetrathiocino donors and fluorine allows for extended interactions that are responsible for solid‐state crystal packing. 相似文献
159.
Giannessi L Bacci A Bellaveglia M Briquez F Castellano M Chiadroni E Cianchi A Ciocci F Couprie ME Cultrera L Dattoli G Filippetto D Del Franco M Di Pirro G Ferrario M Ficcadenti L Frassetto F Gallo A Gatti G Labat M Marcus G Moreno M Mostacci A Pace E Petralia A Petrillo V Poletto L Quattromini M Rau JV Ronsivalle C Rosenzweig J Rossi AR Rossi Albertini V Sabia E Serluca M Spampinati S Spassovsky I Spataro B Surrenti V Vaccarezza C Vicario C 《Physical review letters》2011,106(14):144801
We report the first experimental implementation of a method based on simultaneous use of an energy chirp in the electron beam and a tapered undulator, for the generation of ultrashort pulses in a self-amplified spontaneous emission mode free-electron laser (SASE FEL). The experiment, performed at the SPARC FEL test facility, demonstrates the possibility of compensating the nominally detrimental effect of the chirp by a proper taper of the undulator gaps. An increase of more than 1 order of magnitude in the pulse energy is observed in comparison to the untapered case, accompanied by FEL spectra where the typical SASE spiking is suppressed. 相似文献
160.