8 research outputs found

    A Multi-User Carrier Structure for Deploying Pegasus-Launched Micro-Satellites

    Get PDF
    Now that the viability of the Pegasus air launched booster has been demonstrated, it is possible, and indeed appropriate, to devise methods for exploiting the launcher so that it can launch multiple micro-satellites. Such spacecraft may be launched for a single user, or the capacity of a single launcher may be divided among multiple users. In fact, not all of the satellites on a single launch need to be placed into the same orbit. This paper describes a concept, developed by OSC, to place multiple micro-satellites into various orbits using a single Pegasus launch vehicle. The concept makes use of separable \u27\u27pallets which may be stacked, one on top of the other within the Pegasus fairing. Each pallet can have an integral propulsion system and may transport from one to six micro-satellites into an orbit modified from the reference orbit provided by the launch vehicle. Examples are given as to how the system may be used to implement a variety of mission options. If a constellation of communications satellites are deployed by this approach, global coverage can be provided at what is believed to be the lowest cast available today. The mechanical and propulsion system designs of the pallet are discussed and user constraints are reviewed. The performance capability of the Pegasus vehicle is reviewed as it impacts the individual micro-satellite payload mass

    Have fishes had their chips? The dilemma of threatened fishes

    No full text

    Gene therapy: light is finally in the tunnel

    No full text

    Antiinflammatory therapy with canakinumab for atherosclerotic disease

    No full text
    BACKGROUND: Experimental and clinical data suggest that reducing inflammation without affecting lipid levels may reduce the risk of cardiovascular disease. Yet, the inflammatory hypothesis of atherothrombosis has remained unproved. METHODS: We conducted a randomized, double-blind trial of canakinumab, a therapeutic monoclonal antibody targeting interleukin-1β, involving 10,061 patients with previous myocardial infarction and a high-sensitivity C-reactive protein level of 2 mg or more per liter. The trial compared three doses of canakinumab (50 mg, 150 mg, and 300 mg, administered subcutaneously every 3 months) with placebo. The primary efficacy end point was nonfatal myocardial infarction, nonfatal stroke, or cardiovascular death. RESULTS: At 48 months, the median reduction from baseline in the high-sensitivity C-reactive protein level was 26 percentage points greater in the group that received the 50-mg dose of canakinumab, 37 percentage points greater in the 150-mg group, and 41 percentage points greater in the 300-mg group than in the placebo group. Canakinumab did not reduce lipid levels from baseline. At a median follow-up of 3.7 years, the incidence rate for the primary end point was 4.50 events per 100 person-years in the placebo group, 4.11 events per 100 person-years in the 50-mg group, 3.86 events per 100 person-years in the 150-mg group, and 3.90 events per 100 person-years in the 300-mg group. The hazard ratios as compared with placebo were as follows: in the 50-mg group, 0.93 (95% confidence interval [CI], 0.80 to 1.07; P=0.30); in the 150-mg group, 0.85 (95% CI, 0.74 to 0.98; P=0.021); and in the 300-mg group, 0.86 (95% CI, 0.75 to 0.99; P=0.031). The 150-mg dose, but not the other doses, met the prespecified multiplicity-adjusted threshold for statistical significance for the primary end point and the secondary end point that additionally included hospitalization for unstable angina that led to urgent revascularization (hazard ratio vs. placebo, 0.83; 95% CI, 0.73 to 0.95; P=0.005). Canakinumab was associated with a higher incidence of fatal infection than was placebo. There was no significant difference in all-cause mortality (hazard ratio for all canakinumab doses vs. placebo, 0.94; 95% CI, 0.83 to 1.06; P=0.31). CONCLUSIONS: Antiinflammatory therapy targeting the interleukin-1β innate immunity pathway with canakinumab at a dose of 150 mg every 3 months led to a significantly lower rate of recurrent cardiovascular events than placebo, independent of lipid-level lowering. Copyright © 2017 Massachusetts Medical Society
    corecore