Imaging of small-scale features on 433 Eros from NEAR: evidence for a complex regolith.

On 25 October 2000, the Near Earth Asteroid Rendevous (NEAR)-Shoemaker spacecraft executed a low-altitude flyover of asteroid 433 Eros, making it possible to image the surface at a resolution of about 1 meter per pixel. The images reveal an evolved surface distinguished by an abundance of ejecta blocks, a dearth of small craters, and smooth material infilling some topographic lows. The subdued appearance of craters of different diameters and the variety of blocks and different degrees of their burial suggest that ejecta from several impact events blanketed the region imaged at closest approach and led to the building up of a substantial and complex regolith consisting of fine materials and abundant meter-sized blocks.

Effects of outcome-driven insurance reimbursement on short-term weight control.

CONTEXT: Although most health insurers exclude coverage of weight control therapy, one local insurer offered partial reimbursement of the cost of a weight control program, using an incentive plan. OBJECTIVE: To determine whether outcome-driven insurer-based reimbursement improves participation in a weight control program and short-term weight loss outcomes. DESIGN: Cohort follow-up study between January 1998 and February 2001. SETTING: Community weight management program operated by an academic medical center. SUBJECTS: Obese participants who had the potential for reimbursement (Group A, n=25) and participants in the same program classes (Group B, n=100) who had no possibility for reimbursement. Subjects in Group B were selected from among 206 potential participants using a propensity score to match them with subjects in Group A on age, gender, ethnicity, starting BMI, starting weight, and educational, economic, and demographic variables. INTERVENTION: Group lifestyle-based weight management program. The insurer reimbursed half the cost of the program to obese participants who met minimum weight criteria, paid the program fee at enrollment, attended > or =10 of the 12 classes, and lost > or =6% of initial body weight after 12 weeks. MAIN OUTCOME MEASURES: Participation rates and weight loss outcomes. RESULTS: Group A subjects attended significantly more classes (mean+/-s.d.: 10.1+/-1.8 vs 8.2+/-2.5, P<0.001) and lost more weight than Group B subjects (6.1+/-3.1 vs 3.7+/-3.6%, P=0.002). While 84% of Group A subjects attended > or =10 classes, only 37% of Group B subjects did so (P<0.001); 56% of Group A subjects lost > or =6% of body weight, but only 20% of Group B subjects did so (P<0.001); 56% of Group A subjects achieved both the class attendance and weight loss goals, but only 14% of Group B subjects did so (P<0.001). Logistic regression estimated that Group A subjects had 8.2 times the odds of attending > or =10 classes and 4.5 times the odds of losing > or =6% of body weight of Group B subjects, after controlling for class attendance. CONCLUSIONS: Insurer-based reimbursement that is contingent upon initial financial commitment on the part of the patient, consistent program participation, and successful weight loss is associated with significantly better short-term weight control outcomes.

The landing of the NEAR-Shoemaker spacecraft on asteroid 433 Eros.

The NEAR-Shoemaker spacecraft was designed to provide a comprehensive characterization of the S-type asteroid 433 Eros (refs 1,2,3), an irregularly shaped body with approximate dimensions of 34 x 13 x 13 km. Following the completion of its year-long investigation, the mission was terminated with a controlled descent to its surface, in order to provide extremely high resolution images. Here we report the results of the descent on 12 February 2001, during which 70 images were obtained. The landing area is marked by a paucity of small craters and an abundance of 'ejecta blocks'. The properties and distribution of ejecta blocks are discussed in a companion paper. The last sequence of images reveals a transition from the blocky surface to a smooth area, which we interpret as a 'pond'. Properties of the 'ponds' are discussed in a second companion paper. The closest image, from an altitude of 129 m, shows the interior of a 100-m-diameter crater at 1-cm resolution.