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141.
Scientists and educators at Baylor College of Medicine are using space life sciences research areas as themes for middle school science and health instructional materials. This paper discusses study findings of the most recent unit, Food and Fitness, which teaches concepts related to energy and nutrition through guided inquiry. Results of a field test involving more than 750 students are reported. Use of the teaching materials resulted in significant knowledge gains by students as measured on a pre/post assessment administered by teachers. In addition, an analysis of the time spent by each teacher on each activity suggested that it is preferable to conduct all of the activities in the unit with students rather than allocating the same total amount of time on just a subset of the activities.  相似文献   
142.
The present paper discusses the use of the transformed Eulerian (or “residual”) mean-flow formulation, the Eliassen-Palm flux, and Ertel's potential vorticity to provide an increased understanding of wave, mean-flow interactions, and constituent transport processes in the stratosphere. Temperature and ozone data retrieved from radiance profiles obtained by the LIMS instrument on the Nimbus 7 satellite are utilized in conjunction with these theoretical concepts for the interpretation of phenomena that occurred during the major and minor warmings of January-February 1979. The results illustrate the insight provided by these concepts and demonstrate that useful diagnostic quantities can be derived from global satellite temperature fields.  相似文献   
143.
The International Solar-Terrestrial Physics (ISTP) program will provide simultaneous coordinated scientific measurements from most of the major areas of geospace including specific locations on the Earth's surface. This paper describes the comprehensive ISTP ground science data handling system which has been developed to promote optimal mission planning and efficient data processing, analysis and distribution. The essential components of this ground system are the ISTP Central Data Handling Facility (CDHF), the Information Processing Division's Data Distribution Facility (DDF), the ISTP/Global Geospace Science (GGS) Science Planning and Operations Facility (SPOF) and the NASA Data Archive and Distribution Service (NDADS).The ISTP CDHF is the one place in the program where measurements from this wide variety of geospace and ground-based instrumentation and theoretical studies are brought together. Subsequently, these data will be distributed, along with ancillary data, in a unified fashion to the ISTP Principal Investigator (PI) and Co-Investigator (CoI) teams for analysis on their local systems. The CDHF ingests the telemetry streams, orbit, attitude, and command history from the GEOTAIL, WIND, POLAR, SOHO, and IMP-8 Spacecraft; computes summary data sets, called Key Parameters (KPs), for each scientific instrument; ingests pre-computed KPs from other spacecraft and ground basel investigations; provides a computational platform for parameterized modeling; and provides a number of data services for the ISTP community of investigators. The DDF organizes the KPs, decommutated telemetry, and associated ancillary data into products for duistribution to the ISTP community on CD-ROMs. The SPOF is the component of the GGS program responsible for the development and coordination of ISTP science planning operations. The SPOF operates under the direction of the ISTP Project Scientist and is responsible for the development and coordination of the science plan for ISTP spacecraft. Instrument command requests for the WIND and POLAR investigations are submitted by the PIs to the SPOF where they are checked for science conflicts, forwarded to the GSFC Command Management Syntem/Payload Operations Control Center (CMS/POCC) for engineering conflict validation, and finally incorporated into the conflict-free science operations plan. Conflict resolution is accomplished through iteration between the PIs, SPOF and CMS and in consultation with the Project Scientist when necessary. The long term archival of ISTP KP and level-zero data will be undertaken by NASA's National Space Science Data Center using the NASA Data Archive and Distribution Service (NDADS). This on-line archive facility will provide rapid access to archived KPs and event data and includes security features to restrict access to the data during the time they are proprietary.  相似文献   
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146.
The nematode Caenorhabditis elegans, a popular organism for biological studies, is being developed as a model system for space biology. The chemically defined liquid medium, C. elegans Maintenance Medium (CeMM), allows axenic cultivation and automation of experiments that are critical for spaceflight research. To validate CeMM for use during spaceflight, we grew animals using CeMM and standard laboratory conditions onboard STS-107, space shuttle Columbia. Tragically, the Columbia was destroyed while reentering the Earth's atmosphere. During the massive recovery effort, hardware that contained our experiment was found. Live animals were observed in four of the five recovered canisters, which had survived on both types of media. These data demonstrate that CeMM is capable of supporting C. elegans during spaceflight. They also demonstrate that animals can survive a relatively unprotected reentry into the Earth's atmosphere, which has implications with regard to the packaging of living material during space flight, planetary protection, and the interplanetary transfer of life.  相似文献   
147.
Bains W 《Astrobiology》2004,4(2):137-167
It has been widely suggested that life based around carbon, hydrogen, oxygen, and nitrogen is the only plausible biochemistry, and specifically that terrestrial biochemistry of nucleic acids, proteins, and sugars is likely to be "universal." This is not an inevitable conclusion from our knowledge of chemistry. I argue that it is the nature of the liquid in which life evolves that defines the most appropriate chemistry. Fluids other than water could be abundant on a cosmic scale and could therefore be an environment in which non-terrestrial biochemistry could evolve. The chemical nature of these liquids could lead to quite different biochemistries, a hypothesis discussed in the context of the proposed "ammonochemistry" of the internal oceans of the Galilean satellites and a more speculative "silicon biochemistry" in liquid nitrogen. These different chemistries satisfy the thermodynamic drive for life through different mechanisms, and so will have different chemical signatures than terrestrial biochemistry.  相似文献   
148.
Gerstenmaier W 《Acta Astronautica》2004,54(11-12):777-778
This introductory address provides a brief overview and a timeline for construction of the International Space Station, beginning with the July 2000 launch of the Russian Service Module, Zvezda, and ending with the Mission STS-112.  相似文献   
149.
InSight Mars Lander Robotics Instrument Deployment System   总被引:1,自引:0,他引:1  
The InSight Mars Lander is equipped with an Instrument Deployment System (IDS) and science payload with accompanying auxiliary peripherals mounted on the Lander. The InSight science payload includes a seismometer (SEIS) and Wind and Thermal Shield (WTS), heat flow probe (Heat Flow and Physical Properties Package, HP3) and a precision tracking system (RISE) to measure the size and state of the core, mantle and crust of Mars. The InSight flight system is a close copy of the Mars Phoenix Lander and comprises a Lander, cruise stage, heatshield and backshell. The IDS comprises an Instrument Deployment Arm (IDA), scoop, five finger “claw” grapple, motor controller, arm-mounted Instrument Deployment Camera (IDC), lander-mounted Instrument Context Camera (ICC), and control software. IDS is responsible for the first precision robotic instrument placement and release of SEIS and HP3 on a planetary surface that will enable scientists to perform the first comprehensive surface-based geophysical investigation of Mars’ interior structure. This paper describes the design and operations of the Instrument Deployment Systems (IDS), a critical subsystem of the InSight Mars Lander necessary to achieve the primary scientific goals of the mission including robotic arm geology and physical properties (soil mechanics) investigations at the Landing site. In addition, we present test results of flight IDS Verification and Validation activities including thermal characterization and InSight 2017 Assembly, Test, and Launch Operations (ATLO), Deployment Scenario Test at Lockheed Martin, Denver, where all the flight payloads were successfully deployed with a balloon gravity offload fixture to compensate for Mars to Earth gravity.  相似文献   
150.
During the first half of November 2004, many solar flares and coronal mass ejections (CMEs) were associated with solar active region (AR) 10696. This paper attempts to identify the solar and interplanetary origins of two superstorms which occurred on 8 and 10 November with peak intensities of Dst = −373 nT and −289 nT, respectively. Southward interplanetary magnetic fields within a magnetic cloud (MC), and a sheath + MC were the causes of these two superstorms, respectively. Two different CME propagation models [Gopalswamy, N., Yashiro, S., Kaiser, M.L. et al. Predicting the 1-AU arrival times of coronal mass ejections. J. Geophys. Res. 106, 29207–29219, 2001; Gopalswamy, N.S., Lara, A., Manoharan, P.K. et al. An empirical model to predict the 1-AU arrival of interplanetary shocks. Adv. Space Res. 36, 2289–2294, 2005] were employed to attempt to identify the solar sources. It is found that the models identify several potential CMEs as possible sources for each of the superstorms. The two Gopalswamy et al. models give the possible sources for the first superstorm as CMEs on 2330 UT 4 November 2004 or on 1454 UT 5 November 2004. For the second superstorm, the possible solar source was a CME that on 0754 UT 5 November 2004 or one that occurred on 1206 UT 5 November 2004. We note that other propagation models sometimes agree and other times disagree with the above results. It is concluded that during high solar/interplanetary activity intervals such as this one, the exact solar source is difficult to identify. More refined propagation models are needed.  相似文献   
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