Suchergebnisse

Knowledge of water depth is a crucial for planning military amphibious operations. Bathymetry from remote sensing with multispectral or hyperspectral imagery provides an opportunity to acquire water depth data faster than traditional hydrographic survey methods without the need to deploy a hydrographic survey vessel. It also provides a means of collecting bathymetric data covertly. This research explores two techniques for deriving bathymetry and assesses them for use by those involved in providing support to military operations. To support this aim a fieldwork campaign was undertaken in May, 2000, in northern Queensland. The fieldwork collected various inherent and apparent water optical properties and was concurrent with airborne hyperspectral imagery collection, space-based multispectral imagery collection and a hydrographic survey. The water optical properties were used to characterise the water and to understand how they affect deriving bathymetry from imagery. The hydrographic data was used to assess the performance of the bathymetric techniques. Two methods for deriving bathymetry were trialled. One uses a ratio of subsurface irradiance reflectance at two wavelengths and then tunes the result with known water depths. The other inverts the radiative transfer equation utilising the optical properties of the water to derive water depth. Both techniques derived water depth down to approximately six to seven metres. At that point the Cowley Beach waters became optically deep. Sensitivity analysis of the inversion method found that it was most sensitive to errors in vertical attenuation Kd and to errors in transforming the imagery into subsurface irradiance reflectance, R(0-) units. Both techniques require a priori knowledge to derive depth and a more sophisticated approach would be required to determine water depth without prior knowledge of the area of interest. This research demonstrates that water depth can be accurately mapped with optical techniques in less than ideal optical conditions. It also ...

Mindfulness-based stress-reduction courses were offered in drug units in six Massachusetts Department of Corrections prisons. A total of 1,350 inmates completed the 113 courses. Evaluation assessments were held before and after each course, and highly significant pre- to post-course improvements were found on widely accepted self-report measures of hostility, self-esteem, and mood disturbance. Improvements for women were greater than those for men, and improvements were also greater for men in a minimum-security, pre-release facility than for those in four medium-security facilities. The results encourage further study and wider use of mindfulness-based stress reduction in correctional facilities.

OBJECTIVE: Posttraumatic stress disorder (PTSD) is often difficult to treat, and many patients do not achieve full remission. Complementary and integrative health approaches, such as mindfulness meditation, are intended to be integrated with evidence-based treatment. This study examined the efficacy of mindfulness-based stress reduction (MBSR) in the treatment of PTSD in U.S. military veterans. METHODS: Veterans with a diagnosis of PTSD (N=214) were randomly assigned to either 90-minute group MBSR or present-centered group therapy (PCGT) for eight weeks. Follow-up assessments were obtained at baseline and weeks 3, 6, 9 (primary endpoint), and 16. RESULTS: Both the MBSR and PCGT groups achieved significant improvement in PTSD as measured by the Clinician-Administered PTSD Scale for DSM-IV (CAPS-IV), with no statistically significant differences between groups. However, compared with PCGT, the MBSR group showed a statistically significant improvement in PTSD on the self-reported PTSD Checklist for DSM-IV over the nine weeks. This difference was not maintained posttreatment, at week 16. Strengths of the study include its large sample size, multisite design, active control group, single-blind outcome ratings, fidelity monitoring, large minority representation, and randomized approach. The study was limited by its high attrition rate and low representation of women. CONCLUSION: Both MBSR and PCGT appear to have beneficial effects in treating PTSD in veterans, with greater improvement observed in self-reported PTSD symptoms in the MBSR group. No differences between groups were observed on the CAPS-IV scale.