Graffiti's cut-vertex lower bound for the independence number

Let $G$ be a graph, let $\alpha(G)$ be its independence number, and let $c(G)$ be the number of cut-vertices of $G$. Graffiti's cut-vertex conjecture.

$$\alpha(G) \geq 1+\frac{c(G)}{2}$$

The paper verifies this inequality for the graph classes considered there using bounds on their cut-vertices and independence numbers, but the general conjecture remains open in the source.