601 research outputs found
ROSIsat
As the cost of sending satellites into space continues to drive down, the use of CubeSats for orbital missions continues to rise. Even though these satellites are smaller than traditional satellites, they still provide the ability to take on important science-based missions at a fraction of the cost. The Radiation Orbital Shielding Investigation satellite (ROSIsat) previously known as Project Hermes, will be the first fully student-built satellite for Embry-Riddle’s Daytona Beach campus. The main research mission of ROSIsat consists of shielding onboard memory modules from space radiation using various materials. These materials include simulated Martian and Lunar regolith. To send a student-built CubeSat to space, the ROSIsat team is designing and integrating the majority of the satellite’s components in-house. These in-house components include the CubeSat’s chassis, on-board computer, magnetorquer and payload electronics.. ROSIsat will provide students with educational, technical, scientific, and legal knowledge that can be applied in their respective futures
Radiation Orbital Shielding Investigation Satellite
In the last twenty years, CubeSats and similar small satellites have become increasingly popular, offering a cost-effective way to conduct important scientific activities in low Earth orbit when compared to traditional satellites. These compact satellites serve various purposes, including scientific research, education, technology demonstrations, and commercial applications like communication networks. The Radiation Orbital Shielding Investigation Satellite (ROSIsat) is a 1U CubeSat project specifically designed to study the effectiveness of different materials in shielding against radiation in space. To aid in the development of ROSIsat, some CubeSat components will be produced on-site, while more complex parts will be sourced externally. The main goal of ROSIsat is to carry out experiments related to radiation shielding, which is crucial for aerospace missions. The team plans to test nine different materials, including simulants of lunar and Martian regolith, to improve spacecraft protection during future missions to these celestial bodies. ROSIsat\u27s launch will be facilitated through a rideshare service such as Spaceflight, Nanoracks, or NASA\u27s CubeSat Launch Initiative Program. The data collected from these experiments will enhance the safety protocols for future space exploration missions. Ultimately, the insights gained from ROSIsat\u27s findings will have tangible implications for upcoming space endeavors
PHP51 Characterization Of Injectable Medication Errors In The Hospital Setting: A Retrospective Database Analysis
Development of a rotating gravity gradiometer for earth orbit applications (AAFE)
Some preliminary mission studies are described along with the design, fabrication, and test of a breadboard model of an earth orbital, rotating gravity gradiometer with a design goal of 10 to the minus 11th power/sec sq (0.01 EU) in a 35-sec integration time. The proposed mission uses a Scout vehicle to launch one (or two orthogonally oriented) spin-stabilized satellites into a 330-km circular polar orbit some 20 days before an equinox. During the short orbital lifetime, the experiment would obtain two complete maps of the gravity gradient field with a resolution approaching 270 km (degree 75). The breadboard model of the gradiometer demonstrated a combined thermal and electronic noise threshold of 0.015 EU per data channel. The design changes needed to reduce the noise to less than 0.01 EU were identified. Variations of the sensor output signal with temperature were experimentally determined and a suitable method of temperature compensation was developed and tested. Other possible error sources, such as sensor interaction with satellite dynamics and magnetic fields, were studied analytically and shown to be small
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Impact of Irrigation Strategies on Tomato Root Distribution and Rhizosphere Processes in an Organic System.
Root exploitation of soil heterogeneity and microbially mediated rhizosphere nutrient transformations play critical roles in plant resource uptake. However, how these processes change under water-saving irrigation technologies remains unclear, especially for organic systems where crops rely on soil ecological processes for plant nutrition and productivity. We conducted a field experiment and examined how water-saving subsurface drip irrigation (SDI) and concentrated organic fertilizer application altered root traits and rhizosphere processes compared to traditional furrow irrigation (FI) in an organic tomato system. We measured root distribution and morphology, the activities of C-, N-, and P-cycling enzymes in the rhizosphere, the abundance of rhizosphere microbial N-cycling genes, and root mycorrhizal colonization rate under two irrigation strategies. Tomato plants produced shorter and finer root systems with higher densities of roots around the drip line, lower activities of soil C-degrading enzymes, and shifts in the abundance of microbial N-cycling genes and mycorrhizal colonization rates in the rhizosphere of SDI plants compared to FI. SDI led to 66.4% higher irrigation water productivity than FI, but it also led to excessive vegetative growth and 28.3% lower tomato yield than FI. Our results suggest that roots and root-microbe interactions have a high potential for coordinated adaptation to water and nutrient spatial patterns to facilitate resource uptake under SDI. However, mismatches between plant needs and resource availability remain, highlighting the importance of assessing temporal dynamics of root-soil-microbe interactions to maximize their resource-mining potential for innovative irrigation systems
Multimedia performance evaluation of ethernet and token ring media access protocols: a network comparison
This paper and accompanying project examines which type of time-division multiplexing media access protocol, the Carrier Sense Multiple Access (CSMA) of Ethernet or the token passing of token ring, is best able to fulfill the stringent isochronous performance demands required of today's resource-hungry multimedia networks, specifically the requirements of high throughput, low latency and jitter, and minimal error rates. Using performance bounds accepted by other researchers as sufficient to ensure quality isochronous transmission, that of (1) the throughput rate being equal to or less than the playback rate; (2) the latency in transmitting each packet ranging from 20 to 400 milliseconds and the variance or jitter being less than 80 milliseconds; and (3) the rate of lost packets ranging from 0.01--1.001, this paper approaches a solution first from the theoretical and then integrates into the final conclusion an analytical, C++ software evaluation test component that models network performance under optimum conditions. The immediate benefit of the entire study is the identification of one media access protocol, Ethernet or Token Ring, over its counterpart as being superior for isochronous applications as defined by the above performance requirements, and the long-term consequence of this identification will be facilitating for future network designers, including those of digital libraries, the selection of the best network architecture for their multimedia environments
Management information systems: an information portal for a major with limitless interpretations
Management Information Systems often referred to as MIS is the people-oriented use of computers in business. MIS is both a field of study and a career path. It combines the foundations of computing, analysis, and business in to one field of study. MIS is a major that is growing in popularity; however, it is still unknown to many undergraduates. This thesis includes both research and creative aspects. The information gathered by research was used to generate the requirements for an information portal relating to the MIS program at the University of Northern Iowa (UNI). A portal is a one stop shop for information, resources, and tools relating to a specific topic, in this case, MIS. The primary purpose of the information portal is to be a resource of vital information relating to the MIS program at UNI. This portal is directed towards three primary audiences: prospective students, current students, and alumni. The portal provides information relating to what MIS is, why to choose MIS as a major, what MIS majors can do, and what the MIS program at UNI entails. In addition, the portal provides current undergraduates with key resources for success such as potential employers, what alumni have done, and job opportunities.
An information portal for the MIS program at the College of Business Administration at UNI (also referred to as UNIBusiness) does already exist; however, there are some issues with the current portal. The existing portal has not been maintained in some time and as such, it is not always the best source of information. In addition, technology has changed greatly in the just the past few years which has rendered the existing portal outdated. Currently the existing portal is not a centralized information source; information relating to MIS is currently scatted across the UNIBusiness site. Finally, the desires and expectations of students have changed greatly over the past few years. Since the portal is geared primarily towards students, it must meet their desires and expectations. It is a combination of these factors that prompted this thesis, the creation of an information portal for the MIS program at UNI
Mechanistic features of CAG•CTG repeat contractions in cultured cells revealed by a novel genetic assay
Trinucleotide repeats (TNRs) undergo high frequency mutagenesis to cause at least 15 neurodegenerative diseases. To understand better the molecular mechanisms of TNR instability in cultured cells, a new genetic assay was created using a shuttle vector. The shuttle vector contains a promoter-TNR-reporter gene construct whose expression is dependent on TNR length. The vector harbors the SV40 ori and large T antigen gene, allowing portability between primate cell lines. The shuttle vector is propagated in cultured cells, then recovered and analyzed in yeast using selection for reporter gene expression. We show that (CAG•CTG)(25−33) contracts at frequencies as high as 1% in 293T and 293 human cells and in COS-1 monkey cells, provided that the plasmid undergoes replication. Hairpin-forming capacity of the repeat sequence stimulated contractions. Evidence for a threshold was observed between 25 and 33 repeats in COS-1 cells, where contraction frequencies increased sharply (up 720%) over a narrow range of repeat lengths. Expression of the mismatch repair protein Mlh1 does not correlate with repeat instability, suggesting contractions are independent of mismatch repair in our system. Together, these findings recapitulate certain features of human genetics and therefore establish a novel cell culture system to help provide new mechanistic insights into CAG•CTG repeat instability
Buabin Oil Palm Outgrower Project
Thesis (M.C.P.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 2009.Cataloged from PDF version of thesis.Includes bibliographical references (p. 59-64).Globally, there are about 500 million small farms from which two billion people derive their livelihoods. These farmers face a host of challenges to access both domestic and international markets. This thesis examines the Buabin Oil Palm Outgrower Project as a case of small holder integration into the supply chain of Unilever Ghana, a multinational agribusiness company. In partnership with the public sector, the private sector and a development agency donor, Unilever Ghana is developing 3,000 hectares of oil palm through an outgrower scheme, in which the farmer beneficiaries maintain ownership of their land. I find that the key actors' experiences in the project - even in this early stage, the third year of a five-year implementation phase - demonstrate most importantly that there is not one engineered solution for working with small farmers. Each of the actors' strong motivations but diverse, and sometimes conflicting, agendas combined with logistical challenges require that Unilever Ghana be flexible and adaptable, contrary to the nature of the standardized model of a multinational. I conclude that agribusiness multinationals require a partner, or locally embedded subsidiary, with local knowledge and international development expertise as a facilitator to bridge the gap between standard corporate models and the complexity of working with small farmers.by Christina PioCosta-Lahue Santini.M.C.P
Partial reconstitution of DNA large loop repair with purified proteins from Saccharomyces cerevisiae
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