68 research outputs found
Effect of time to diagnostic testing for breast, cervical, and colorectal cancer screening abnormalities on screening efficacy: A modeling study
Background: Patients who receive an abnormal cancer screening result require follow-up for diagnostic testing, but the time to follow-up varies across patients and practices. Methods: We used a simulation study to estimate the change in lifetime screening benefits when time to follow-up for breast, cervical, and colorectal cancers was increased. Estimates were based on four independently developed microsimulation models that each simulated the life course of adults eligible for breast (women ages 50–74 years), cervical (women ages 21–65 years), or colorectal (adults ages 50–75 years) cancer screening. We assumed screening based on biennial mammography for breast cancer, triennial Papanicolaou testing for cervical cancer, and annual fecal immunochemical testing for colorectal cancer. For each cancer type, we simulated diagnostic testing immediately and at 3, 6, and 12 months after an abnormal screening exam. Results: We found declines in screening benefit with longer times to diagnostic testing, particularly for breast cancer screening. Compared to immediate diagnostic testing, testing at 3 months resulted in reduced screening benefit, with fewer undiscounted life years gained per 1,000 screened (breast: 17.3%, cervical: 0.8%, colorectal: 2.0% and 2.7%, from two colorectal cancer models), fewer cancers prevented (cervical: 1.4% fewer, colorectal: 0.5% and 1.7% fewer, respectively), and, for breast and colorectal cancer, a less favorable stage distribution. Conclusions: Longer times to diagnostic testing after an abnormal screening test can decrease screening effectiveness, but the impact varies substantially by cancer type. Impact: Understanding the impact of time to diagnostic testing on screening effectiveness can help inform quality improvement efforts. Cancer Epidemiol Biomarkers Prev; 27(2); 158–64. 2017 AACR
FY 1987 Aquatic Species Program: Annual report
The goal of the Department of Energy/Solar Energy Research Institute Aquatic Species Program is to develop the technology base to produce liquid fuels from microalagae at prices competitive with conventional alternatives. Microalgae are unusual plants that can accumulate large quantities of oil and can thrive in high-salinity water, which currently has no competing uses. The algal oils, in turn, are readily converted into gasoline and diesel fuels. The best site for successful microalgae production was determined to be the US desert Southwest, with potential applications to other warm areas. Aggressive research is needed, but the improvements required are attainable. The four prime research areas in the development of this technology are growth and production, engineering design, harvesting, and conversion. Algae are selected for three criteria: tolerance to environmental fluctuations, high growth rates, and high lipid production. From 1982 to 1986, the program collected more than 3000 strains of microalgae that are more than twice as tolerant to temperature and salinity fluctuation than the initial strains. Productivity has been increased by a factor of two in outdoor culture systems since 1982, and lipid content has also been increased from 20% of body weight in 1982 to greater than 66% of body weight in 1987. Research programs are ongoing in lipid biochemistry and genetic engineering so that ultimately strains can be modified and improved to combine their best characteristics. An outdoor test facility is being built in Roswell, New Mexico
The BepiColombo mission: An outstanding tool for investigating the Hermean environment
International audienceMercury possesses a weak, internal, global magnetic field that supports a small magnetosphere populated by charged particles originating from the solar wind, the planet's exosphere and surface layers. Mercury's exosphere is continuously refilled and eroded through a variety of chemical and physical processes acting in the planet's surface and environment. Using simultaneous two-point measurements from two satellites, ESA's future mission BepiColombo will offer an unprecedented opportunity to investigate magnetospheric and exospheric dynamics at Mercury as well as their interactions with solar radiation and interplanetary dust. The expected data will provide important insights into the evolution of a planet in close proximity of a star. Many payload instruments aboard the two spacecraft making up the mission will be completely, or partially, devoted to studying the close environment of the planet as well as the complex processes that govern it. Coordinated measurements by different onboard instruments will permit a wider range of scientific questions to be addressed than those that could be achieved by the individual instruments acting alone. Thus, an important feature of the BepiColombo mission is that simultaneous two-point measurements can be implemented at a location in space other than the Earth. These joint observations are of key importance because many phenomena in Mercury's environment are temporarily and spatially varying. In the present paper, we focus on some of the exciting scientific goals achievable during the BepiColombo mission through making coordinated observations
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