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1.
Carello Giuliana Landa Paolo Tnfani Elena Testi Angela 《Central European Journal of Operations Research》2022,30(1):159-187
Central European Journal of Operations Research - In the past years, the number of patients in need of chemotherapy treatments has been constantly increasing. Chemotherapy treatments must be... 相似文献
2.
Marco Marletta 《Advances in Computational Mathematics》1994,2(2):155-184
This paper discusses the numerical solution of eigenvalue problems for Hamiltonian systems of ordinary differential equations.
Two new codes are presented which incorporate the algorithms described here; to the best of the author’s knowledge, these
are the first codes capable of solving numerically such general eigenvalue problems. One of these implements a new new method
of solving a differential equation whose solution is a unitary matrix. Both codes are fully documented and are written inPfort-verifiedFortran 77, and will be available in netlib/aicm/sl11f and netlib/aicm/sl12f. 相似文献
3.
Peptidic aminopeptidase inhibitors, bestatin, phebestin and probestin have been prepared by stereo- and regiocontrolled reactions from a common α,β-epoxy ester precursor. 相似文献
4.
5.
The CD curves of a set of condensed γ-butyrolactones have been investigated. A simple correlation between the sign of the Cotton effect (CE) and the configuration of C can be deduced from the resulting data. 相似文献
6.
[reaction: see text] Marine diatoms produce alpha,beta,gamma,delta-unsaturated aldehydes that have detrimental effects on the reproduction of their natural predators. The production of these defensive metabolites is suggested to involve enzymatic oxidation of polyunsaturated fatty acids. In this paper, feeding experiments with labeled precursor provide clear evidence in support of the origin of octadienals 1 and 2 from 6,9,12-hexadecatrienoic acid (5), thus proving the involvement of novel lipoxygenase/lyase activity for the oxidation of C(16) fatty acids. 相似文献
7.
Bianco G Schmitt-Kopplin P Crescenzi A Comes S Kettrup A Cataldi TR 《Analytical and bioanalytical chemistry》2003,375(6):799-804
The glycoalkaloid content of transgenic potatoes was evaluated by an optimised method based on non-aqueous capillary electrophoresis coupled on-line with electrospray ionization-mass spectrometry (NACE-ESI-MS). The potato material consisted of tubers from a conventional cv. Désirée and from three lines of modified plants resistant, intermediate and susceptible to infection by potato virus Y (PVY). The main glycoalkaloids were confirmed to be alpha-solanine and alpha-chaconine with parent ion masses m/z 852 and 868, respectively. In addition, an unknown minor peak at m/z 850.6 was found both in conventional (control) and susceptible line potato tubers. Such a compound exhibited an MS(2) spectrum with fragments ions at 704 and 396 m/z derived by loss of two ions, i.e. m/z 146 and 307, most likely corresponding to a rhamnose unit and a [glucose-(rhamnose)(2)] moiety, respectively. Up to 30-80-fold higher concentrations of total glycoalkaloids were found in the peel compared to flesh samples of all tubers examined. TGA content was nearly doubled in peel samples of resistant compared to control lines, and these levels were lower than the limit recommended for food safety, i.e. 20-60 mg of TGA per 100 g fresh weight. Moreover, it was established that tubers produced by virus-resistant clones are substantially equivalent in glycoalkaloid contents to those produced by conventional potato varieties. 相似文献
8.
The complex (1) has been prepared and its structure determined. Complex1 is the first stable thioether derivative of a metal carbonyl containing only cobalt as metal. It crystallizes in the monoclinic P21/c space group, witha = 13.975( 4 ),b = 11.363( 3 ),c = 14.686(2)A, = 112.25(2)°,V = 2158.5(7)A3.Z = 4. The solution using direct methods and the anisotropic refinement of all nonhydrogen atoms led toR = 0.039,wR = 0.041 for 3296 reflections with F> 4.0(F) Analogous but less stable complexes are formed with 1,6-diphenyl-2,5-dithiahexane and the crown thioether 1,4,7-trithiacyclonane, the latter functioning either as a bidenlate or a tridentate ligand. 相似文献
9.
Giuliana Gervasio Domenica Marabello Andrea Secco 《Journal of organometallic chemistry》2004,689(1):35-42
The reaction of Ru3(CO)12 with but-2-yn-1,4-diol (HOCH2CCCH2OH, BUD) in CH3OH/KOH followed by acidification with HCl leads to four products, one of which has been identified as the title complex (μ-Cl)Ru3(CO)9[μ3-η4-H2CCC(H)CH2]. This is an open cluster containing a bridging Cl atom on the open side and a C4H5 moiety bound to all the metals. The structure of the complex has been determined by X-ray analysis.The thermal reaction of Ru3(CO)12 with BUD has been revisited for a comparison with the results in alkaline solution. The main product is the allylic derivative HRu3(CO)9[HCCHCCHO]. 相似文献
10.
Carnazza S Satriano C Guglielmino S Marletta G 《Journal of colloid and interface science》2005,289(2):386-393
The influence of the surface chemical structure and related physicochemical properties on the adhesion of P. aeruginosa has been studied for moderately hydrophobic polymers and for hydrophilic surfaces obtained by O2-plasma treatments and 50 keV Ar+ beam irradiation of poly(hydroxymethylsiloxane) and poly(ethyleneterephthalate). The surface chemical structure has been obtained by X-ray photoelectron spectroscopy, the roughness was measured by atomic force microscopy, and the surface free energy was evaluated from contact angle measurements for all the polymer substrates before and after the irradiation treatments. It is shown that a massive and unusually fast secretion of exopolysaccharides onto highly polar surfaces, corresponding to the formation of complex three-dimensional multilayers (i.e., biofilm-like structures), occurs already after 2 h of incubation. It is suggested that such highly polar surfaces can operate either by promoting, by means of a still unknown biomolecular mechanism, an early gene expression process or by mimicking the P. aeruginosa cellular walls. 相似文献