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71.
Uniqueness of the Topology on Spaces of Vector-Valued Functions 总被引:1,自引:0,他引:1
Let be a topological space without isolated points, let E bea topological linear space which is continuously embedded intoa product of countably boundedly generated topological linearspaces, and let X be a linear subspace of C(, E). If a C()is not constant on any open subset of and aX X, then it isshown that there is at most one F-space topology on X that makesthe multiplication by a continuous. Furthermore, if U is a subsetof C() which separates strongly the points of and UX X, thenit is proved that there is at most one F-space topology on Xthat makes the multiplication by a continuous for each a U. These results are applied to the study of the uniqueness ofthe F-space topology and the continuity of translation invariantoperators on the Banach space L1(G, E) for a noncompact locallycompact group G and a Banach space E. Furthermore, the problemsof the uniqueness of the F-algebra topology and the continuityof epimorphisms and derivations on F-algebras and some algebrasof vector-valued functions are considered. 相似文献
72.
73.
Calderbank AR; Cameron PJ; Kantor WM; Seidel JJ 《Proceedings London Mathematical Society》1997,75(2):436-480
When m is odd, spreads in an orthogonal vector space of type+(2m + 2,2) are related to binary Kerdock codes and extremalline-sets in 2m + 1 with prescribed angles. Spreads in a 2m-dimensionalbinary symplectic vector space are related to Kerdock codesover Z4 and extremal line-sets in with prescribed angles. These connections involve binary, realand complex geometry associated with extraspecial 2-groups.A geometric map from symplectic to orthogonal spreads is shownto induce the Gray map from a corresponding Z4-Kerdock codeto its binary image. These geometric considerations lead tothe construction, for any odd composite m, of large numbersof Z4-Kerdock codes. They also produce new Z4-linear Kerdockand Preparata codes. 1991 Mathematics Subject Classification:primary 94B60; secondary 51M15, 20C99. 相似文献
74.
The relative stabilities of thymidine-3',5'-diphosphoric acid (1) derived isomeric cations and radicals were calculated and key geometric parameters were thoroughly analyzed. The most probable sites of a hydride-ion (1', 2', 5-Me) and H-atom (4', 5', 5-Me) abstraction were identified, thus allowing prediction of the regioselectivity of potential damage to the deoxyribose ring and thymine moiety caused by carcinogenic agents of electrophilic and radical nature. [structure: see text] 相似文献
75.
Every random function holomorphic in mean on an open subset of the complex field is equivalent to a random function with almost all its paths holomorphic on .
76.
A domino reaction that is pericyclic in nature is thought to be triggered upon treatment of alkenynol 10 with arylsulfenyl chlorides. The process comprises an ordered sequence of sigmatropic rearrangements: a reversible [2,3]-allyl sulfenate to allyl sulfoxide shift, followed by a [2,3]-propargyl sulfenate to allenyl sulfoxide rearrangement, and last a stereodifferentiating [1,5]-sigmatropic hydrogen migration leading to polyene 13. The occurrence of the C7 to C11 hydrogen migration has been demonstrated by labeling experiments. The double diastereoselection of the [1,5]-sigmatropic hydrogen shift to afford a single isomer of the final polyene 13 is thought to arise from a combination of the electronic effect of the sulfoxide at one terminus, and the steric effect imparted by the bulky trimethylcyclohexenyl substituent at the other terminus. The overall process thus constitutes a stereoselective synthesis of an E,Z,Z-triene fragment from an alkenynol and, in particular, a retinoid with the 7E,9Z,11Z,13E configuration on the conjugated polyenic side chain. Application of this method to the synthesis of retinoids, including labeled analogues, is straightforward. 相似文献
77.
Danila Cianciosi Johura Ansary Tamara Y. Forbes-Hernandez Lucia Regolo Denise Quinzi Santos Gracia Villar Eduardo Garcia Villena Kilian Tutusaus Pifarre Jos M. Alvarez-Suarez Maurizio Battino Francesca Giampieri 《Molecules (Basel, Switzerland)》2021,26(9)
Cancer stem cells (CSCs) are a rare tumor subpopulation with high differentiation, proliferative and tumorigenic potential compared to the remaining tumor population. CSCs were first discovered by Bonnet and Dick in 1997 in acute myeloid leukemia. The identification and isolation of these cells in this pioneering study were carried out through the flow cytometry, exploiting the presence of specific cell surface molecular markers (CD34+/CD38−). In the following years, different strategies and projects have been developed for the study of CSCs, which are basically divided into surface markers assays and functional assays; some of these techniques also allow working with a cellular model that better mimics the tumor architecture. The purpose of this mini review is to summarize and briefly describe all the current methods used for the identification, isolation and enrichment of CSCs, describing, where possible, the molecular basis, the advantages and disadvantages of each technique with a particular focus on those that offer a three-dimensional culture. 相似文献
78.
Ivn Montenegro Jorge Moreira Ingrid Ramírez Fernando Dorta Elizabeth Snchez Juan Felipe Alfaro Manuel Valenzuela Carlos Jara-Gutirrez Ociel Muoz Matias Alvear Enrique Werner Alejandro Madrid Joan Villena Michael Seeger 《Molecules (Basel, Switzerland)》2021,26(1)
An evaluation of antioxidant and anticancer activity was screened in Leptocarpha rivularis DC flower extracts using four solvents (n-hexane (Hex), dichloromethane (DCM), ethyl acetate (AcOEt), and ethanol (EtOH)). Extracts were compared for total extract flavonoids and phenol contents, antioxidant activity (2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH), ferric reducing antioxidant potential (FRAP), total reactive antioxidant properties (TRAP) and oxygen radical absorbance capacity (ORAC)) across a determined value of reduced/oxidized glutathione (GSH/GSSG), and cell viability (the sulforhodamine B (SRB) assay). The most active extracts were analyzed by chromatographic analysis (GC/MS) and tested for apoptotic pathways. Extracts from Hex, DCM and AcOEt reduced cell viability, caused changes in cell morphology, affected mitochondrial membrane permeability, and induced caspase activation in tumor cell lines HT-29, PC-3, and MCF-7. These effects were generally less pronounced in the HEK-293 cell line (nontumor cells), indicating clear selectivity towards tumor cell lines. We attribute likely extract activity to the presence of sesquiterpene lactones, in combination with other components like steroids and flavonoids. 相似文献
79.
The semileptonic decay width of heavy baryons such as (Λ
b
→ Λcev) has been estimated in the framework of a nonrelativistic field theoretic quark model where four component quark field
operators along with a harmonic oscillator wave function are used to describe translationally invariant hadronic states. The
present estimation does not make an explicit use of heavy quark symmetry and has a reasonable agreement with the experimentally
measured decay width, polarisation ratio and form factors with the harmonic oscillator radii and quark momentum distribution
inside the hadron as free parameters. 相似文献
80.