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The friction and lateral stiffness of the contact between an atomic force microscopy (AFM) probe tip and an atomically flat dolomite (104) surface were investigated in contact with two aqueous solutions that were in equilibrium and supersaturated with respect to dolomite, respectively. The two aqueous solutions yielded negligible differences in friction at the native dolomite−water interface. However, the growth of a Ca-rich film from the supersaturated solution, revealed by X-ray reflectivity measurements, altered the probe−dolomite contact region sufficiently to observe distinct friction forces on the native dolomite and the film-covered surface regions. Quantitative friction−load relationships demonstrated three physically distinct load regimes for applied loads up to 200 nN. Similar friction forces were observed on both surfaces below 50 nN load and above 100 nN load. The friction forces on the two surfaces diverged at intermediate loads. Quantitative measurements of dynamic friction forces at low load were consistent with the estimated energy necessary to dehydrate the surface ions, whereas differences in mechanical properties of the Ca-rich film and dolomite surfaces were evidently important above 50 nN load. Attempts to fit the quantitative stiffness−load data using a Hertzian contact mechanical model based on bulk material properties yielded physically unrealistic fitting coefficients, suggesting that the interfacial contact region must be explicitly considered in describing the static and dynamic contact mechanics of this and similar systems. [ABSTRACT FROM AUTHOR]

Objective: Adults with a history of sexual abuse often suffer many long-term consequences. It is important that therapists be able to provide effective treatment to address the host of issues that are presented in therapy by adult survivors of childhood sexual abuse (CSA). In order to provide the best possible treatment, therapists should know which treatments are most effective.Method: This paper provides a critique of the outcome research of 13 studies (six uncontrolled and seven controlled) on the treatment of adults who suffered childhood sexual abuse and discusses specific methodological strategies that can enhance the quality of such research in the future.Results: Although many of the studies contain methodological limitations, the results generally indicate that group treatment helps reduce symptomatology in the short-term and at follow-up.Conclusion: Although outcome research has not been published on specific individual or conjoint treatment approaches for adult survivors of CSA, several outcome studies have found group treatment to be effective in the recovery of female CSA survivors. [Copyright &y& Elsevier]