Micro-and nanopositioning systems are widely used in the field of nanotechnology for probing, imaging, and increasingly for processing. This two-part set of papers presents a MEMS-scale parallel-kinematics mechanism, designed to achieve pure spatial (X, Y and Z) translation. With three independent kinematic chains connecting the end-effector to the base, a fully functional mechanism with axis actuation and displacement sensing is realized in a double device layer ("oreo") SOI wafer using only conventional, microfabrication processes. This paper, the first in a two paper set, presents the mechanism, specially designed for scalable microfabrication. It analyzes its kinematics and dynamics, and characterizes its workspace. Part II of this set of papers describes the detailed design, fabrication, characterization and control of the devices.

Background: Physical activity (PA) is central to the global agenda for the prevention on noncommunicable diseases (NCDs). Although 80% of NCDs occur in low-to-middle-income countries, the evidence on PA comes mainly from high-income countries. In this context, the report card for Colombia is an advocacy tool to help in the translation of evidence into concrete actions. The aims of this paper were two-fold: to present the methodology used to develop the first Report Card on Physical Activity in Colombian Children and Youth and to summarize the results. Methods: Twelve indicators of PA were graded using numerical grades (5, highest, to 1, lowest) based on data from national surveys and policy documents. Results: National policy and obesity indicators were graded "4," while departmental policy and overweight indicators were graded "3." Overall PA levels, sports participation, sedentary behaviors and nongovernment initiatives were graded "2," and school influence was graded "1." Active transportation, active play, low cardiorespiratory fitness, and family and community influence received an incomplete. Conclusion: PA levels are low and sedentary behaviors are high in Colombian children and youth. Although the prevalence of obesity in Colombia is lower compared with other Latin American countries, it is increasing. A rich legal framework and availability of institutional arrangements provide unique opportunities to bridge the gap between knowledge and practice that need to be evaluated.

Mesoscale electromechanical systems find applications in fields such as medical instrumentation, soft robotics, microscopy, flexible electronics and imagining. This paper implements the printed circuit MEMS (PC-MEMS) process [1]for the fabrication of a 'pop-up' flexure-based mesoscale systemthat exploits the simplicity of 2-D manufacturing techniques such assheet-metal operations and laser cutting to realize a 3-D mechanism. The fabrication of a laminated Delta robot with prismatic actuation is presented to exemplify this process. A working device with actuation and functional components such as linear guides, stepper motors and limit switches is designed and fully realized. Because the mechanism is popped out of the plane to achieve its3D shape, we present a stiffness analysis to arrive at the out-of-plane (or 'pop-out') angles that the planar system must accommodate so that constraints/limits on actuator torque/force can be can satisfied while producing an operational system. The simplicity of the processes makes it a candidate for the use in the emerging open-source hardware technologies forfabricating low-cost, complex, electromechanical systems.

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