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At least 289 records · Page 16

The association between neighborhood obesogenic factors and prostate cancer risk and mortality: the Southern Community Cohort Study

Background: Prostate cancer is one of the leading causes of cancer-related mortality among men in the United States. We examined the role of neighborhood obesogenic attributes on prostate cancer risk and mortality in the Southern Community Cohort Study (SCCS). Methods: From the total of 34,166 SCCS male participants, 28,356 were included in the analysis. We assessed the relationship between neighborhood obesogenic factors [neighborhood socioeconomic status (nSES) and neighborhood obesogenic environment indices including the restaurant environment index, the retail food environment index, parks, recreational facilities, and businesses] and prostate cancer risk and mortality by controlling for individual-level factors using a multivariable Cox proportional hazards model. We further stratified prostate cancer risk analysis by race and body mass index (BMI). Results: Median follow-up time was 133 months [interquartile range (IQR): 103, 152], and the mean age was 51.62 (SD: ± 8.42) years. There were 1,524 (5.37%) prostate cancer diagnoses and 98 (6.43%) prostate cancer deaths during follow-up. Compared to participants residing in the wealthiest quintile, those residing in the poorest quintile had a higher risk of prostate cancer (aHR = 1.32, 95% CI 1.12–1.57, p = 0.001), particularly among non-obese men with a BMI < 30 (aHR = 1.46, 95% CI 1.07–1.98, p = 0.016). The restaurant environment index was associated with a higher prostate cancer risk in overweight (BMI ≥ 25) White men (aHR = 3.37, 95% CI 1.04–10.94, p = 0.043, quintile 1 vs. None). Obese Black individuals without any neighborhood recreational facilities had a 42% higher risk (aHR = 1.42, 95% CI 1.04–1.94, p = 0.026) compared to those with any access. Compared to residents in the wealthiest quintile and most walkable area, those residing within the poorest quintile (aHR = 3.43, 95% CI 1.54–7.64, p = 0.003) or the least walkable area (aHR = 3.45, 95% CI 1.22–9.78, p = 0.020) had a higher risk of prostate cancer death. Conclusion: Living in a lower-nSES area was associated with a higher prostate cancer risk, particularly among Black men. Restaurant and retail food environment indices were also associated with a higher prostate cancer risk, with stronger associations within overweight White individuals. Finally, residing in a low-SES neighborhood or the least walkable areas were associated with a higher risk of prostate cancer mortality.

60 APPLIED LIFE SCIENCES↗

SCIMON: Scientific Inspiration Machines Optimized for Novelty

We explore and enhance the ability of neu- ral language models to generate novel scien- tific directions grounded in literature. Work on literature-based hypothesis generation has traditionally focused on binary link prediction— severely limiting the expressivity of hypothe- ses. This line of work also does not focus on optimizing novelty. We take a dramatic depar- ture with a novel setting in which models use as input background contexts (e.g., problems, experimental settings, goals), and output natu- ral language ideas grounded in literature. We present SCIMON, a modeling framework that uses retrieval of “inspirations” from past scien- tific papers, and explicitly optimizes for novelty by iteratively comparing to prior papers and up- dating idea suggestions until sufficient novelty is achieved. Comprehensive evaluations reveal that GPT-4 tends to generate ideas with over- all low technical depth and novelty, while our methods partially mitigate this issue. Our work represents a first step toward evaluating and developing language models that generate new ideas derived from the scientific literature.

Ji, Heng↗

Thermal control of the International Ultraviolet Explorer

The International Ultraviolet Explorer (IUE) is a large astronomical observatory scheduled to be placed in a three-axis stabilized synchronous orbit in the fourth quarter of 1977. The thermal control system consists of multilayer insulation, ammonia-filled grooved heat pipes, bimetallic actuated louvers, and assorted commandable heaters. The spacecraft must operate over a 135-deg solar aspect range and must be able to survive an 85-min.-zero power eclipse. It has a design lifetime of three years. To verify the thermal design, an Engineering Test Unit (ETU) was subjected to a thermal balance test in the Solar Environment Simulator (SES) at the Goddard Space Flight Center (GSFC). Heater skins were utilized to simulate four solar aspect angles, and various internal power settings were used to simulate different operational cases. Temperatures obtained corresponded within 5C of predicted values, thus verifying the thermal analytical model. In addition, two 85-min.-eclipse periods were successfully completed verifying that the thermal design of the IUE was adequate for this mission requirement.

Skladany, J. T.↗

KU-Band rendezvous radar performance computer simulation model

The preparation of a real time computer simulation model of the KU band rendezvous radar to be integrated into the shuttle mission simulator (SMS), the shuttle engineering simulator (SES), and the shuttle avionics integration laboratory (SAIL) simulator is described. To meet crew training requirements a radar tracking performance model, and a target modeling method were developed. The parent simulation/radar simulation interface requirements, and the method selected to model target scattering properties, including an application of this method to the SPAS spacecraft are described. The radar search and acquisition mode performance model and the radar track mode signal processor model are examined and analyzed. The angle, angle rate, range, and range rate tracking loops are also discussed.

Griffin, J. W.↗

Automotive Stirling engine development program

The major accomplishments were the completion of the Basic Stirling Engine (BSE) and the Stirling Engine System (SES) designs on schedule, the approval and acceptance of those designs by NASA, and the initiation of manufacture of BSE components. The performance predictions indicate the Mod II engine design will meet or exceed the original program goals of 30% improvement in fuel economy over a conventional Internal Combustion (IC) powered vehicle, while providing acceptable emissions. This was accomplished while simultaneously reducing Mod II engine weight to a level comparable with IC engine power density, and packaging the Mod II in a 1985 Celebrity with no external sheet metal changes. The projected mileage of the Mod II Celebrity for the combined urban and highway CVS cycle is 40.9 mpg which is a 32% improvement over the IC Celebrity. If additional potential improvements are verified and incorporated in the Mod II, the mileage could increase to 42.7 mpg.

Ernst, W.↗

A Stirling engine analysis method based upon moving gas nodes

A Lagrangian nodal analysis method for Stirling engines (SEs) is described, validated, and applied to a conventional SE and an isothermalized SE (with fins in the hot and cold spaces). The analysis employs a constant-mass gas node (which moves with respect to the solid nodes during each time step) instead of the fixed gas nodes of Eulerian analysis. The isothermalized SE is found to have efficiency only slightly greater than that of a conventional SE.

Martini, W. R.↗

History of visual systems in the Systems Engineering Simulator

The Systems Engineering Simulator (SES) houses a variety of real-time computer generated visual systems. The earliest machine dates from the mid-1960's and is one of the first real-time graphics systems in the world. The latest acquisition is the state-of-the-art Evans and Sutherland CT6. Between the span of time from the mid-1960's to the late 1980's, tremendous strides have been made in the real-time graphics world. These strides include advances in both software and hardware engineering. The purpose is to explore the history of the development of these real-time computer generated image systems from the first machine to the present. Hardware advances as well as software algorithm changes are presented. This history is not only quite interesting but also provides us with a perspective with which we can look backward and forward.

Christianson, David C.↗

The test facility requirements for the thermal vacuum thermal balance test of the Cosmic Background Explorer Observatory

The Cosmic Background Explorer Observatory (COBE) underwent a thermal vacuum thermal balance test in the Space Environment Simulator (SES). This was the largest and most complex test ever conducted at this facility. The 4 x 4 m (13 x 13 ft) spacecraft weighed approx. 2223 kg (4900 lbs) for the test. The test set up included simulator panels for the inboard solar array panels, simulator panels for the flight cowlings, Sun and Earth Sensor stimuli, Thermal Radio Frequency Shield heater stimuli and a cryopanel for thermal control in the Attitude Control System Shunt Dissipator area. The fixturing also included a unique 4.3 m (14 ft) diameter Gaseous Helium Cryopanel which provided a 20 K environment for the calibration of one of the spacecraft's instruments, the Differential Microwave Radiometer. This cryogenic panel caused extra contamination concerns and a special method was developed and written into the test procedure to prevent the high buildup of condensibles on the panel which could have led to backstreaming of the thermal vacuum chamber. The test was completed with a high quality simulated space environment provided to the spacecraft. The test requirements, test set up, and special fixturing are described.

Milam, Laura J.↗

Report of the panel on the land surface: Process of change, section 5

The panel defined three main areas of study that are central to the Solid Earth Science (SES) program: climate interactions with the Earth's surface, tectonism as it affects the Earth's surface and climate, and human activities that modify the Earth's surface. Four foci of research are envisioned: process studies with an emphasis on modern processes in transitional areas; integrated studies with an emphasis on long term continental climate change; climate-tectonic interactions; and studies of human activities that modify the Earth's surface, with an emphasis on soil degradation. The panel concluded that there is a clear requirement for global coverage by high resolution stereoscopic images and a pressing need for global topographic data in support of studies of the land surface.

Adams, John B.↗

Test facility requirements for the thermal vacuum thermal balance test of the Cosmic Background Explorer Observatory

The Cosmic Background Explorer Observatory (COBE) underwant a thermal vacuum thermal balance test in the Space Environment Simulator (SES). This was the largest and most complex test ever conducted at this facility. The 4 x 4 m (13 x 13 ft) spacecraft weighed approx. 2223 kg (4900 lbs) for the test. The test set up included simulator panels for the inboard solar array panels, simulator panels for the flight cowlings, Sun and Earth Sensor stimuli, Thermal Radio Frequency Shield heater stimuli and a cryopanel for thermal control in the Attitude Control System Shunt Dissipator area. The fixturing also included a unique 4.3 m (14 ft) diameter Gaseous Helium Cryopanel which provided a 20 K environment for the calibration of one of the spacecraft's instruments, the Differential Microwave Radiometer. This cryogenic panel caused extra contamination concerns and a special method was developed and written into the test procedure to prevent the high buildup of condensibles on the panel which could have led to backstreaming of the thermal vacuum chamber. The test was completed with a high quality simulated space environment provided to the spacecraft. The test requirements, test set up, and special fixturing are described.

Milam, Laura J.↗

From diffusion pumps to cryopumps: The conversion of GSFC's space environment simulator

The SES (Space Environmental Simulator), largest of the Thermal Vacuum Facilities at The Goddard Space Flight Center, recently was converted from an oil diffusion pumped chamber to a Cryopumped chamber. This modification was driven by requirements of flight projects. The basic requirement was to retain or enhance the operational parameters of the chamber such as pumping speed, ultimate vacuum, pump down time, and thermal system performance. To accomplish this task, seventeen diffusion pumps were removed and replaced with eight 1.2 meter (48 inch) diameter cryopumps and one 0.5 meter (20 inch) turbomolecular pump. The conversion was accomplished with a combination of subcontracting and in-house efforts to maximize the efficiency of implementation.

Cary, Ron↗

Results of prototype software development for automation of shuttle proximity operations

The effort involves demonstration of expert system technology application to Shuttle rendezvous operations in a high-fidelity, real-time simulation environment. The JSC Systems Engineering Simulator (SES) served as the test bed for the demonstration. Rendezvous applications were focused on crew procedures and monitoring of sensor health and trajectory status. Proximity operations applications were focused on monitoring, crew advisory, and control of the approach trajectory. Guidance, Navigation, and Control areas of emphasis included the approach, transition and stationkeeping guidance, and laser docking sensor navigation. Operator interface displays for monitor and control functions were developed. A rule-based expert system was developed to manage the relative navigation system/sensors for nominal operations and simple failure contingencies. Testing resulted in the following findings; (1) the developed guidance is applicable for operations with LVLH stabilized targets; (2) closing rates less than 0.05 feet per second are difficult to maintain due to the Shuttle translational/rotational cross-coupling; (3) automated operations result in reduced propellant consumption and plume impingement effects on the target as compared to manual operations; and (4) braking gates are beneficial for trajectory management. A versatile guidance design was demonstrated. An accurate proximity operations sensor/navigation system to provide relative attitude information within 30 feet is required and redesign of the existing Shuttle digital autopilot should be considered to reduce the cross-coupling effects. This activity has demonstrated the feasibility of automated Shuttle proximity operations with the Space Station Freedom. Indications are that berthing operations as well as docking can be supported.

Hiers, Hal↗

Results of prototype software development for automation of shuttle proximity operations

A Rendezvous Expert System (REX) was implemented on a Symbolics 3650 processor and integrated with the 6 DOF, high fidelity Systems Engineering Simulator (SES) at the NASA Johnson Space Center in Houston, Texas. The project goals were to automate the terminal phase of a shuttle rendezvous, normally flown manually by the crew, and proceed automatically to docking with the Space Station Freedom (SSF). The project goals were successfully demonstrated to various flight crew members, managers, and engineers in the technical community at JSC. The project was funded by NASA's Office of Space Flight, Advanced Program Development Division. Because of the complexity of the task, the REX development was divided into two distinct efforts. One to handle the guidance and control function using perfect navigation data, and another to provide the required visuals for the system management functions needed to give visibility to the crew members of the progress being made towards docking the shuttle with the LVLH stabilized SSF.

Hiers, Harry K.↗

[STS-26 EVA Rescue Training]

This video shows astronauts Covey, Hilmers, and Hauck training in SES. It involves a simulated EVA rescue using the RMS. Training demonstrates the movement of a free-floating astronaut for grapple with the arm.

Source record↗

Status report of RMS active damping augmentation

A status report of Remote Manipulator System (RMS) active damping augmentation is presented. Topics covered include: active damping augmentation; benefits of RMS ADA; simulated payload definition; sensor and actuator definition; ADA control law design; Shuttle Engineering Simulator (SES) real-time simulation; and astronaut evaluation.

Gilbert, Mike↗

Automation and Upgrade of Thermal System for Large 38-Year-Young Test Facility

The Goddard Space Flight Center's Space Environment Simulator (SES) facility has been improved by the upgrade of its thermal control hardware and software. This paper describes the preliminary design process, funding constraints, and the proposed enhancements as well as the installation details, the testing difficulties, and the overall benefits realized from this upgrade. The preliminary design process was discussed in a paper presented in October 1996 and will be recapped in this paper to provide background and comparison to actual product. Structuring the procurement process to match the funding constraints allowed Goddard to enhance its capabilities in an environment of reduced budgets. The installation of the new system into a location that has been occupied for over 38 years was one of the driving design factors for the size of the equipment. The installation was completed on time and under budget. The tuning of the automatic sequences for the new thermal system to the existing shroud system required more time and ultimately presented some setbacks to the vendor and the final completion of the system. However, the end product and its benefits to Goddard's thermal vacuum test portfolio will carry the usefulness of this facility well into the next century.

Webb, Andrew T.↗

Automation and Upgrade of Thermal System for Large 38-Year Young Test Facility

The Goddard Space Flight Center's Space Environment Simulator (SES) facility has been improved by the upgrade of its thermal control hardware and software. This paper describes the preliminary design process, funding constraints, and the proposed enhancements as well as the installation details, the testing difficulties, and the overall benefits realized from this upgrade. The preliminary design process was discussed in a paper presented in October 1996 and will be recapped in this paper to provide background and comparison to actual product. Structuring the procurement process to match the funding constraints allowed Goddard to enhance its capabilities in an environment of reduced budgets. The installation of the new system into a location that has been occupied for over 38-years was one of the driving design factors for the size of the equipment. The installation was completed on-time and under budget. The tuning of the automatic sequences for the new thermal system to the existing shroud system required more time and ultimately presented some setbacks to the vendor and the final completion of the system. However, the end product and its benefits to Goddard's thermal vacuum test portfolio will carry the usefulness of this facility well into the next century.

Webb, Andrew↗

STS-112 Crew Training Clip

Footage shows the crew of STS-112 (Jeffrey Ashby, Commander; Pamela Melroy, Pilot; David Wolf, Piers Sellers, Sandra Magnus, and Fyodor Yurchikhin, Mission Specialists) during several parts of their training. The video is arranged into short segments. In 'Topside Activities at the NBL', Wolf and Sellers are fitted with EVA suits for pool training. 'Pre-Launch Bailout Training in CCT II' shows all six crew members exiting from the hatch on a model of a shuttle orbiter cockpit. 'EVA Training in the VR Lab' shows a crew member training with a virtual reality simulator, interspersed with footage of Magnus, and Wolf with Melroy, at monitors. There is a 'Crew Photo Session', and 'Pam Melroy and Sandy Magnus at the SES Dome' also features a virtual reality simulator. The final two segments of the video involve hands-on training. 'Post Landing Egress at the FFT' shows the crew suiting up into their flight suits, and being raised on a harness, to practice rapelling from the cockpit hatch. 'EVA Prep and Post at the ISS Airlock' shows the crew assembling an empty EVA suit onboard a model of a module. The crew tests oxygen masks, and Sellers is shown on an exercise bicycle with an oxygen mask, with his heart rate monitored (not shown).

Source record↗