Let $\lambda$ and $\mu$ be solid sequence spaces. For a sequence of modulus functions $\Phi =\left({\varphi }_k\right)$ let $\lambda \left(\Phi \right)=\{x=\left(x_k\right)({\varphi }_k\left(\right|x_k\left|\right))\in \lambda \}$. Given another sequence of modulus functions $\Psi =\left({\psi }_k\right)$, we characterize the continuity of the superposition operators $P_f$ from $\lambda \left(\Phi \right)$ into $\mu \left(\Psi \right)$ for some Banach sequence spaces $\lambda$ and $\mu$ under the assumptions that the moduli ${\varphi }_k$$(k\in ...$

We transform the concept of p-summing operators, 1≤ p < ∞, to the more general setting of nonlinear Banach space operators. For 1-summing operators on B(Σ,X)-spaces having weak integral representations we generalize the Grothendieck-Pietsch domination principle. This is applied for the characterization of 1-summing Hammerstein operators on C(S,X)-spaces. For p-summing Hammerstein operators we derive the existence of control measures and p-summing extensions to B(Σ,X)-spaces.

Let ⟨X,Y⟩ be a duality pair of M-spaces X,Y of measurable functions from Ω ⊂ ℝ ⁿ into ${ℝ}^d$. The paper deals with Y-weak cluster points ϕ̅ of the sequence $\varphi (·,z_j\left(·\right))$ in X, where $z_j:\Omega \to {ℝ}^m$ is measurable for j ∈ ℕ and $\varphi :\Omega \times {ℝ}^m\to {ℝ}^d$ is a Carathéodory function. We obtain general sufficient conditions, under which, for some negligible set $A_{\varphi }$, the integral $I(\varphi ,{\nu }_x):={\int }_{{ℝ}^m}\varphi (x,\lambda )d{\nu }_x\left(\lambda \right)$ exists for $x\in \Omega \setminus A_{\varphi }$ and $\varphi ̅\left(x\right)=I(\varphi ,{\nu }_x)$ on $\Omega \setminus A_{\varphi }$, where $\nu ={{\nu }_x}_{x\in \Omega }$ is a measurable-dependent family of Radon probability measures on ${ℝ}^m$.