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UFFO-pathfinder is a pioneering space mission to observe the early evolution of Gamma-ray Bursts using a fast slewing strategy. It consists of the Slewing Mirror Telescope, for rapid pointing at UV/optical wavelengths and the UFFO Burst Alert and Trigger Telescope. It has a total weight of ~ 20 kg and will be launched on-board the Russian Lomonosov satellite at the end of 2015. The instrumental details of UFFO-pathfinder and its performance are discussed briefly here.

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One of the least documented and understood aspects of gamma-ray bursts (GRBs) is the rise phase of the optical light curve. The Ultra-Fast Flash Observatory (UFFO) is an effort to address this question through extraordinary opportunities presented by a series of space missions including a small spacecraft observatory. The UFFO is equipped with a fast-response Slewing Mirror Telescope (SMT) that uses a rapidly moving mirror or mirror array to redirect the optical beam rather than slewing the entire spacecraft to aim the optical instrument at the GRB position. The UFFO will probe the early optical rise of GRBs with sub-second response, for the first time, opening a completely new frontier in GRBs and transient studies. Its fast response measurements of the optical emission of dozens of GRBs each year will provide unique probes of the burst mechanism and test the prospect of GRBs as a new standard candle, potentially opening up the z > 10 universe. For the first time we employ a motorized slewing stage in SMT that can point to the event within 1 s after the x-ray trigger provided by the UFFO Burst Alert and Trigger Telescope. These two scientific instruments comprise the UFFO-pathfinder payload, which will be placed onboard the Lomonosov satellite and launched in 2013. The UFFO-pathfinder is the first step of our long-term program of space instruments for rapid-response GRB observations. We describe early photon science, our soon-to-be-launched UFFO-pathfinder hardware and mission, and our next planned mission, the UFFO-100. © IOP Publishing and Deutsche Physikalische Gesellschaft.

One of the least documented and understood aspects of gamma-ray bursts (GRBs) is the rise phase of the optical light curve. The Ultra-Fast Flash Observatory (UFFO) is an effort to address this question through extraordinary opportunities presented by a series of space missions including a small spacecraft observatory. The UFFO is equipped with a fast-response Slewing Mirror Telescope (SMT) that uses a rapidly moving mirror or mirror array to redirect the optical beam rather than slewing the entire spacecraft to aim the optical instrument at the GRB position. The UFFO will probe the early optical rise of GRBs with sub-second response, for the first time, opening a completely new frontier in GRBs and transient studies. Its fast response measurements of the optical emission of dozens of GRBs each year will provide unique probes of the burst mechanism and test the prospect of GRBs as a new standard candle, potentially opening up the z > 10 universe. For the first time we employ a motorized slewing stage in SMT that can point to the event within 1 s after the x-ray trigger provided by the UFFO Burst Alert and Trigger Telescope. These two scientific instruments comprise the UFFO-pathfinder payload, which will be placed onboard the Lomonosov satellite and launched in 2013. The UFFO-pathfinder is the first step of our long-term program of space instruments for rapid-response GRB observations. We describe early photon science, our soon-to-be-launched UFFO-pathfinder hardware and mission, and our next planned mission, the UFFO-100.

Gamma-Ray Bursts (GRBs) are the most energetic explosions in the universe, their optical photonflux rise very quickly, typically within one minute, then fall off gradually. Hundreds of GRBs optical light curveshave been measured since the first discovery of GRB in 1967. However, only a handful of measurements havebeen made within a minute after the gamma ray signal. Because of this drawback, the short-hard type GRBs andrapid-rising GRBs, which may account for 30% of all GRBs, remain practically unexplored. To reach sub-minutetimescales, the Ultra-Fast Flash Observatory (UFFO) uses a rapidly moving mirror to redirect the optical beaminstead of slewing the entire spacecraft. The first realization of this concept is UFFO-pathfinder, which is equippedwith fast-response Slewing Mirror Telescope (SMT) and a UFFO Burst Alert and Trigger Telescope (UBAT).SMT has a slewing mirror to redirect optical photons into a telescope and then record them by an intensified CCD.UBAT uses coded mask to provide X-ray trigger from a GRB and provides the GRB location for SMT. UFFOssub-minute measurements of the optical emission of dozens of GRBs each year will result in a more rigorous testof current internal shock models, probe the extremes of bulk Lorentz factors, provide the first early and detailedmeasurements of fast-rise GRB optical light curves, and help verify the prospect of GRB as a new standard candle.The UFFO-pathfinder is fully integrated with the Lomonosov satellite and is scheduled to be launched in late 2013or early 2014. We will present the latest progress in this conference

Gamma-ray bursts (GRBs) are the most luminous transient events with short intense flashes that have been detected in random directions in the sky once or twice per day. Their durations have been measured in seconds, especially short GRBs with duration of <2 sec. The Ultra-Fast Flash Observatory (UFFO) space mission aims to detect the earliest moments of an explosion which presents the nature of GRBs, resulting into the enhancement of GRB mechanism understanding. The UFFO consists of a couple of wide Field-of-View (FOV) trigger telescopes, a narrow-FOV Slewing Mirror Telescope (SMT) for the fast measurement of the UV-optical photons from GRBs, and a gamma-ray monitor for energy measurement. The triggering is done by the UFFO burst Alert & Trigger telescope (UBAT) using the hard X-ray from GRBs and the UV/optical Trigger Assistant Telescope (UTAT) using the UV/optical photons from GRBs. The UBAT monitors the sky for GRB, and determines their position with sufficient accuracy (10′ at 7.0σ) for follow-up UV/optical observations with the SMT. The primary trigger telescope is based on a fast recognition of position using hard X-ray from GRBs. Whereas the fastest previous experiment, the SWIFT observatory, rarely observed GRB in less than 60 seconds after trigger, the UFFO is designed to begin the UV/optical observations in less than a few seconds after trigger. The SMT uses the novel approach of steering our telescope beam using the rotatable mirror, instead of re-orienting the instrument platform like SWIFT and other previous instruments. The UFFO pathfinder is scheduled to launch into orbit on 2011 November by the Lomonosov spacecraft. This pathfinder is the scaled-down version of UFFO in order to make the first systematic study of early UV/optical light curves, including the rise phase of GRBs. It contains two instruments of UBAT and SMT. It only allows the payload mass of 20 kg and the power consumption of 20 W. The SMT has a fast rotatable mirror, a modified R

Polycaprolactone (PCL) and PCL-based copolymers have shown high potential for drug delivery and tissue engineering applications as degradable biomaterials. However, the degradation of PCL and its copolymers has been reported mostly in the form of films, microspheres and rods for drug delivery devices but not much in the form of scaffolds for tissue engineering applications. The study focuses on the in vitro degradation of scaffolds fabricated with PCL homopolymer and PCL-PEG (polycaprolactone-polyethylene glycol) diblock copolymer using desktop robot-based rapid prototyping (DRBRP) technique. Accelerated degradation was carried out in concentrated NaOH solution to investigate the influence of polymer nature and scaffold architecture on the degradation behavior and kinetics of the scaffolds. Both PCL and PCL-PEG scaffolds realized homogeneous hydrolytic degradation resulting in a consistent molecular weight and mass loss. The consistent material loss caused uniform increase in porosity that decreased the mechanical properties correspondingly. The results suggest that the incorporation of hydrophilic PEG into hydrophobic PCL enhanced the overall hydrophilicity and thus degradability of PCL-PEG copolymer. However, the architectural variation did not influence the degradation kinetics significantly.