Autonomous support for microorganism research in space

A preliminary design for performing on orbit, autonomous research on microorganisms and cultured cells/tissues is presented. An understanding of gravity and its effects on cells is crucial for space exploration as well as for terrestrial applications. The payload is designed to be compatible with the Commercial Experiment Transporter (COMET) launch vehicle, an orbiter middeck locker interface, and with Space Station Freedom. Uplink/downlink capabilities and sample return through controlled reentry are available for all carriers. Autonomous testing activities are preprogrammed with in-flight reprogrammability. Sensors for monitoring temperature, pH, light, gravity levels, vibrations, and radiation are provided for environmental regulation and experimental data collection. Additional experimental data acquisition includes optical density measurement, microscopy, video, and film photography. On-board full data storage capabilities are provided. A fluid transfer mechanism is utilized for inoculation, sampling, and nutrient replenishment of experiment cultures. In addition to payload design, representative experiments were developed to ensure scientific objectives remained compatible with hardware capabilities. The project is defined to provide biological data pertinent to extended duration crewed space flight including crew health issues and development of a Controlled Ecological Life Support System (CELSS). In addition, opportunities are opened for investigations leading to commercial applications of space, such as pharmaceutical development, modeling of terrestrial diseases, and material processing

Grazing Alfalfa: Real Cost of Fear of Bloat

In the Southeast, including legumes like alfalfa and clover in pastures provides many advantages. It reduces the impact of fescue toxicosis, provides free nitrogen, and improves pasture quality leading to increased animal performance. Individual animal performance is greater on grass/legume pastures compared to performance on similar monoculture grass stands. Daily gains for steers grazing clover-fescue swards is improved compared to straight tall fescue pastures (Figure 1). Improved performance is partially due to greater forage intakes. This practice is sound management even though legume bloat is a risk to livestock. If one considers the number of cattle grazing pastures containing legumes worldwide, the “fear of bloat” results in far greater economic losses from low beef cattle gain than the potential losses from bloat itself. In other words, if you don’t incorporate legumes into your pastures, you are leaving money on the table

Heralded Generation of Ultrafast Single Photons in Pure Quantum States

We present an experimental demonstration of heralded single photons prepared in pure quantum states from a parametric downconversion source. It is shown that, through controlling the modal structure of the photon pair emission, one can generate pairs in factorable states and thence eliminate the need for spectral filters in multiple-source interference schemes. Indistinguishable heralded photons were generated in two independent spectrally engineered sources, and, by performing a Hong-Ou-Mandel interference between them without spectral filters at a raw visibility of 94.4%, their purity was measured to be over 95%.Comment: 5 pages, 4 figure

Conditional preparation of single photons using parametric downconversion: A recipe for purity

In an experiment reported recently [Phys. Rev. Lett. 100, 133601 (2008)], we demonstrated that, through group velocity matched parametric downconversion, heralded single photons can be generated in pure quantum states without spectral filtering. The technique relies on factorable photon pair production, initially developed theoretically in the strict collinear regime; focusing - required in any experimental implementation - can ruin this factorability. Here we present the numerical model used to design our single photon sources and minimize spectral correlations in the light of such experimental considerations. Furthermore, we show that the results of our model are in good agreement with measurements made on the photon pairs and give a detailed description of the exact requirements for constructing this type of source.Comment: 27 pages, 14 figures, submitted to NJ

Wavefront Sensing and Control Architecture for the Spherical Primary Optical Telescope (SPOT)

Testbed results are presented demonstrating high-speed image-based wavefront sensing and control for a spherical primary optical telescope (SPOT). The testbed incorporates a phase retrieval camera coupled to a 3-Mirror Vertex testbed (3MV) at the NASA Goddard Space Flight Center. Actuator calibration based on the Hough transform is discussed as well as several supercomputing archtectures for image-based wavefront sensing. Timing results are also presented based on various algorithm implementations using a cluster of 64 TigerShare TSlOl DSP's (digital-signal processors)

Master Grazer: Improving Grazing Management in Kentucky

The Master Grazer Educational Program is the result of funding provided by the Kentucky Agricultural Development Board to educate producers on better utilization of grazing lands to improve livestock production and the profitability of the State. County agriculture and natural resource agents, extension specialists, industry contacts and producers work together to make this program a success. The Master Grazer Educational Program began in 2006 as evening lecture sessions taking place in local extension offices. In 2008, the program grew with the addition of a field session that showcased a farm with successful grazing practices, a farm with underdeveloped grazing practices, and a final session for participants to develop their own grazing system. In 2010, the program was modified into the Applied Master Grazer Program. This program placed more emphasis on the importance of the county agriculture. The agents decided which topics would be covered and administered many areas of the program. The program now consists of a minimum of two evening field sessions in which a farm is showcased for a particular topic, as well as one impact session in which participants can interact and contribute to a producer forum. For the purpose of this article, reporting will be focused on the last two years of the Master Grazer Program. The past few years, events such as Grazing Schools, the Advanced Grazing Schools, and Pasture Walks have been held to discuss timely topics of forage and livestock management. Also, the Master Grazer Program has a newsletter, website, and DVD series