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Abstract: We present two sufficient conditions for normal structure in a Banach space. The first one is given in terms of the new modulus which is a generalization of Gao’s modulus of U-convexity and the second one is given by the presence of full 2-rotundity of the dual space and the WORTH property. [Copyright &y& Elsevier]

Abstract: The structure of the Cesàro function spaces Ces p on both [0,1] and [0, ∞) for 1 < p ≤ ∞ is investigated. We find their dual spaces, which equivalent norms have different description on [0, 1] and [0, ∞).The spaces Ces p for 1 < p < ∞ are not reflexive but strictly convex. They are not isomorphic to any Lq space with 1 ≤ q ≤ ∞. They have “near zero” complemented subspaces isomorphic to lp and “in the middle” contain an asymptotically isometric copy of l 1 and also a copy of L 1[0, 1]. They do not have Dunford-Pettis property but they do have the weak Banach-Saks property. Cesàro function spaces on [0, 1] and [0, ∞) are isomorphic for 1 < p ≤ ∞. Moreover, we give characterizations in terms of p and q when Ces p [0, 1] contains an isomorphic copy of lq . [Copyright &y& Elsevier]

Abstract: We call a subspace Y of a Banach space X a DBR subspace if its unit ball By admits farthest points from a dense set of points of X. In this paper, we study DBR subspaces of C(K). In the process, we study boundaries, in particular, the Choquet boundary of any general subspace of C(K). An infinite compact Hausdorff space K has no isolated point if and only if any finite co-dimensional subspace, in particular, any hyperplane is DBR in C(K). As a consequence, we show that a Banach space X is reflexive if and only if X is a DBR subspace of any superspace. As applications, we prove that any M-ideal or any closed *-subalgebra of C(K) is a DBR subspace of C(K). It follows that C(K) is ball remotal in C(K) **. [Copyright &y& Elsevier]