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71.
The reported synthesis of 3-phcnyl-2H-1,4-benzoxazin-2-one (II) via brominution of o-acel-amidophenyl phcnaeyl ether (Scheme) leads in lael to the 7-bromo-3-phenyl-2H-1,4-benzoxazin-2-ol (VIII). The structure of the other synthetic intermediates is also revised and a one-step synthesis of the lactone II is reported hy condensation of methyl phenylglyoxalale and o-amino-phenol.  相似文献   
72.
Riassunto In questa nota si considerano gli spazi funzionali con norma mista, studiati daA. Benedek eR. Panzone, e vengono date delle condizioni sufficienti perchè una funzione misurabile sia un moltiplicatore dell’integrale di Fourier da a . Tali condizioni sono l’estensione di quelle trovate daP. I. Lizorkin nel caso degli spazi di LebesgueL p (R n ).
Résumé Dans cette note on considère les espaces fonctionnels avec norme mixte, étudiés parA. Benedek etR. Panzone, et l’on obtient quelques conditions suffisantes afin que une fonction mesurable soit un multiplicateur de l’intégral de Fourier. Ces conditions sont la généralisation de ceux découvertes parP. I. Lizorkin dans le cas des espaces de LebesgueL p (R n ).


Lavoro esequito nell’ambito dell’attività dei gruppi di ricerca matematici del C.N.R.  相似文献   
73.
A geometrization of the Yang-Mills field, by which an SU(2) gauge theorybecomes equivalent to a 3-space geometry—or optical system—is examined. Ina first step, ambient space remains Euclidean and current problems on flat spacecan be looked at from a new point of view. The Wu-Yang ambiguity, for example,appears related to the multiple possible torsions of distinct metric-preservingconnections. In a second step, the ambient space also becomes curved. In thegeneric case, the strictly Riemannian metric sector plays the role of an arbitraryhost space, with the gauge potential represented by a contorsion. For some fieldconfigurations, however, it is possible to obtain a purely metric representation.In those cases, if the space is symmetric homogeneous, the Christoffel connectionsare automatically solutions of the Yang-Mills equations.  相似文献   
74.
In this paper we give existence and uniqueness theorems for weak solutions of a mixed initial and boundary value problem with conservative boundary conditions relating to a particular symmetric hyperbolic linear system with discontinuous coefficients. The unicity is proved also for a mixed non linear problem.  相似文献   
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This note describes a procedure for plane higher-curvature path analysis and synthesis. All coefficients have been written in terms of elementary instantaneous invariants. This facilitates the numerical computation of Generalized Burmester Points for a moving link of a planar mechanism in a non-symmetric position. FORTRAN subroutines have been written and a numerical example is provided.
Sommario Si descrive una procedura di analisi e sintesi per meccanismi piani generatori di traiettoria con approssimazione del quarto ordine. Nella formulazione adottata, l'impiego degli invarianti istantanei elementari consente di valutare analiticamente i termini delle equazioni per la ricerca dei punti generalizzati di Burmester. Sono state implementate subroutines in linguaggio FORTRAN ed è stato sviluppato un esempio numerico.

Nomenclature P o velocity pole - inflection circle diameter - angle of rotation of the moving body - r f ,r m radii of curvature of the fixed and moving polodes, respectively - dl infinitesimal arc length measured on the polode - a,b coordinates ofP o , in the canonical reference system1 - a i ,b i i-th derivatives ofa andb, respectively, computed at the initial position (i.e. =0). These are the elementary instantaneous invariants - h,* polar coordinates of the moving point in the canonical reference system (0 ) - radius of curvature of the point-path trajectory - E radius of curvature of the evolute of the point-path trajectory - E /(2) radius of curvature of the evolute of the evolute of the point-path trajectory A canonical reference system is a rectangular right-handed cartesian system having they-axis directed toward inflexion pole, origin in the velocity pole.  相似文献   
77.
We developed a novel and convenient stereoselective path for the preparation of pyrrolo-1,5-benzoxazepinones (PBOs). This innovative route envisaged the employment of (−)-menthol as convenient chiral auxiliary and a key SNAr for the stereoselective preparation of a tertiary aryl–alkyl ether. As a further advancement, we exploited this newly conceived synthetic route for the preparation of 2-substituted PBO analogues to either undergo biological evaluation themselves or give access to a variety of further functionalization options.  相似文献   
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Glucose-6-phosphate dehydrogenase (G6PD) deficiency is one of the most well-known human genetic defects, identified in more than 400 million individuals in the world. To date, no commercial kits are available for the mutation screening of this disease. Seventy G6PD-deficient Italian individuals admitted to the Laboratory of Clinical Molecular Biology of Hospital "Agostino Gemelli" of Rome were screened for the most frequent Italian mutations, by means of allele-specific PCR, followed by restriction fragment length electrophoresis. The present study compares two techniques for the identification of restriction patterns: agarose gel electrophoresis versus Experion system. When the first screening was negative, the entire G6PD gene was sequenced using the ABI 3100 Avant Instrumentation. The G6PD variants identified and their frequencies were the following: G6PD Mediterranean (75.7%), G6PD Seattle (7.1%), G6PD A(-) 202 + 376 (7.1%), and G6PD Cassano (2.8%). In addition, we identified by direct sequencing two new mutations, namely Buenos Aires and Rignano. With the Experion method, the size band determination was more accurate than that obtained by gel electrophoresis. The Experion system resulted as a valid, easy, and reproducible diagnostic method for the screening of G6PD mutation as compared with the agarose electrophoretic analysis.  相似文献   
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