What is the test for determining whether a prison regulation impermissibly infringes on an inmate's constitutional rights?

^2. Four factors are relevant in determining whether a prison regulation impermissibly infringes on an inmate's constitutional rights: (1) whether there is a "valid, rational connection between the prison regulation and the legitimate governmental interest put forward to justify it"; (2) "whether there are alternative means of exercising the right that remain open to prison inmates"; (3) "the impact accommodation of the asserted constitutional right will have on guards and other inmates and on the allocation of prison resources generally"; and (4) the "absence of ready alternatives." Turner v. Safley, 482 U.S. 78, 89-90 (1987) (internal quotations omitted).