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61.
The note extends Lawler’s [E.L. Lawler, A pseudopolynomial algorithm for sequencing jobs to minimize total tardiness, Annals of Discrete Mathematics, 1 (1977) 331–342] fundamental decomposition theorem. This extension serves as a basis for alternate criteria that recognize when the problem is non-decomposable. It also shows that even relaxing a single criterion to a weak inequality may contradict Lawler’s (1977) decomposition theorem. 相似文献
62.
We study a time-non-homogeneous Markov process which arose from free probability, and which also appeared in the study of stochastic processes with linear regressions and quadratic conditional variances. Our main result is the explicit expression for the generator of the (non-homogeneous) transition operator acting on functions that extend analytically to complex domains. 相似文献
63.
Janusz J. Charatonik Wlodzimierz J. Charatonik 《Proceedings of the American Mathematical Society》2002,130(10):3097-3099
Two properties of continua are shown which are strong Whitney reversible while not sequential strong Whitney reversible. This answers an old question of S. B. Nadler, Jr.
64.
Wlodzimierz Augustyniak Jan Wojtczak 《Journal of polymer science. Part A, Polymer chemistry》1980,18(4):1339-1346
Investigations were performed on acetone and benzene-sensitized degradation of triethylene glycol (TEG), polyethylene glycol 400 (PEG 400), and polyethylene glycol 4000 (PEG 4000) in aqueous solutions exposed to irradiation at λ = 254 nm and λ ~ 313 nm. The systems investigated were exposed at 20°C (±1°C) in both deaerated and undeaerated solutions. The course of the photosensitized degradation was examined viscosimetrically. The determined quantum yield (?) of chain scission decreases distinctly as the molecular weight of the polymer rises, irrespective of the wavelength of the light absorbed and deaeration of system exposed. 相似文献
65.
Giorgio Pidello Wlodzimierz M. Tulczyjew 《Annali di Matematica Pura ed Applicata》1987,147(1):249-265
Summary The theory of derivations of differential forms, originally formulated by Frölicher and Nijenhuis [2], is generalized to include derivations which connect differential forms on two different manifolds. This generalized theory is then used to analyze derivations of direct limits of exterior algebras of forms on jet bundles. Such derivations have found applications in the analysis of Lie equations [3], [4] and in the inverse problem of the calculus of variations [6], [7], [8], [9].
This work is a part of a program conducted jointly with ProfessorBenenti at Istituto di Fisica Matematica «J. L. Lagrange» of Torino. The authors are greatly indebted to the Director of the Institute Professor D.Galletto for his interest and encouragement.This work has been supported by Gruppo Nazionale per la Fisica Matematica del Consiglio Nazionale delle Ricerche. 相似文献
Résumé On présente une généralization de la théorie des dérivations des formes extérieures, formulée par Frölicher et Nijenhuis [2], au cas des dérivations qui relient les formes extérieurs sur deux variétés différentes. On utilize ensuite cette théorie généralizée pour étudier les dérivations des limites directes des algèbres des formes extérieures sur les fibrés des jets. Ces dérivations ont été appliquées dans l'analyse des équations de Lie [3], [4] et dans le problème inverse du calcul des variations [6], [7], [8], [9].
This work is a part of a program conducted jointly with ProfessorBenenti at Istituto di Fisica Matematica «J. L. Lagrange» of Torino. The authors are greatly indebted to the Director of the Institute Professor D.Galletto for his interest and encouragement.This work has been supported by Gruppo Nazionale per la Fisica Matematica del Consiglio Nazionale delle Ricerche. 相似文献
66.
67.
Wlodzimierz M. Daniewski Andrzej Wawrzun Maria De Bernardi Giovanni Vidari Paola Vita-Finzi Giovanni Fronza Giuseppina Gatti 《Tetrahedron》1984,40(14):2757-2762
The structures of lactarorufins D and E, two new sesquiterpenes from Lactarius necator, have been elucidated. Conformational analysis of lactarorufins and blennins is discussed. 相似文献
68.
Anthracyclines belong to the anticancer drugs that are widely used in chemotherapy. However, due to their systemic toxicity they also exert dangerous side effects associated mainly with cardiovascular risks. The pathway that is currently often developed is their chemical and physical modification via formation of conjugated or complexed prodrug systems with a variety of nanocarriers that can selectively release the active species in cancer cells. In this study, six new nanoconjugates were synthesized with the use of polyhedral oligosilsesquioxanes [POSS(OH)32] as nanocarriers of the anticancer drugs anthracyclines—doxorubicin (DOX) and daunorubicin (DAU). These prodrug conjugates are also equipped with poly(ethylene glycol) (PEG) moieties of different structure and molecular weight. Water-soluble POSS, succinic anhydride modified (SAMDOX and SAMDAU) with carboxylic function, and PEGs (PEG1, PEG2 and PEGB3) were used for the synthesis. New nanoconjugates were formed via ester bonds and their structure was confirmed by NMR spectroscopy (1H-NMR, 13C-NMR, 1H-13C HSQC, DOSY and 1H-1H COSY), FTIR and DLS. Drug release rate was evaluated using UV-Vis spectroscopy at pH of 5.5. Release profiles of anthracyclines from conjugates 4–9 point to a range of 10 to 75% (after 42 h). Additionally, model NMR tests as well as diffusion ordered spectroscopy (DOSY) confirmed formation of the relevant prodrugs. The POSS-anthracycline conjugates exhibited prolonged active drug release time that can lead to the possibility of lowering administered doses and thus giving them high potential in chemotherapy. Drug release from conjugate 7 after 42 h was approx. 10%, 33% for conjugate 4, 47% for conjugate 5, 6, 8 and 75% for conjugate 9. 相似文献
69.
1H, 1H–1H COSY and 13C NMR techniques were proven as effective methods for the analysis of functionalized doxorubicin (DOX) and daunorubicin (DAU) derivatives. These compounds represent important drug conjugate intermediates that can be coupled to a variety of nanocarriers. NMR spectroscopy was shown to be an efficient method for following the progress of drug modification and can also be useful for evaluation of the functionalized structures purity. Additionally, a correction of the chemical shifts reported in the literature for the relevant drugs e.g. DOX·HCl and DAU·HCl is presented. 相似文献
70.
Optimum sample medium for single-nucleotide polymorphism and mutation detection by capillary electrophoresis 总被引:2,自引:0,他引:2
Capillary electrophoresis (CE) is a versatile analytical platform widely used for nucleic acids analysis. Its applications in research and diagnostics include scanning and screening for mutations and polymorphisms by such reliable methods as single-strand conformation polymorphism (SSCP), heteroduplex analysis (HA), and combined SSCP/HA. This study, aimed at the further development of these methods, is focused on detailed sample-media characteristics. Factors affecting single-strand conformer stability and DNA intake efficiency were analyzed. The sample media optimal for efficient mutation or SNP detection were determined, and complex SSCP-CE patterns arising from unpurified PCR products were explained. It turns out, that the nondenaturing aqueous media assure both efficient DNA intake, and single-strand conformers stability required for the SSCP and combined SSCP/HA. The results of this study are applicable to all these areas of biomedical research, in which capillary electrophoresis is used for the characterization of nucleic acids. 相似文献