12,826 research outputs found
Development of stitching reinforcement for transport wing panels
The NASA Advanced Composites Technology (ACT) program has the objective of providing the technology required to obtain the full benefit of weight savings and performance improvements offered by composite primary aircraft structures. Achieving the objective is dependent upon developing composite materials and structures which are damage tolerant and economical to manufacture. Researchers are investigating stitching reinforcement combined with resin transfer molding to produce materials meeting the ACT program objective. Research is aimed at materials, processes, and structural concepts for application in both transport wings and fuselages, but the emphasis to date has been on wing panels. Empirical guidelines are being established for stitching reinforcement in structures designed for heavy loads. Results are presented from evaluation tests investigating stitching types, threads, and density (penetrations per square inch). Tension strength, compression strength, and compression after impact data are reported
Laboratory studies in ultraviolet solar physics
The research activity comprised the measurement of basic atomic processes and parameters which relate directly to the interpretation of solar ultraviolet observations and to the development of comprehensive models of the component structures of the solar atmosphere. The research was specifically directed towards providing the relevant atomic data needed to perform and to improve solar diagnostic techniques which probe active and quiet portions of the solar chromosphere, the transition zone, the inner corona, and the solar wind acceleration regions of the extended corona. The accuracy with which the physical conditions in these structures can be determined depends directly on the accuracy and completeness of the atomic and molecular data. These laboratory data are used to support the analysis programs of past and current solar observations (e.g., the Orbiting solar Observatories, the Solar Maximum Mission, the Skylab Apollo Telescope Mount, and the Naval Research Laboratory's rocket-borne High Resolution Telescope and Spectrograph). In addition, we attempted to anticipate the needs of future space-borne solar studies such as from the joint ESA/NASA Solar and Heliospheric Observatory (SOHO) spacecraft. Our laboratory activities stressed two categories of study: (1) the measurement of absolute rate coefficients for dielectronic recombination and electron impact excitation; and (2) the measurement of atomic transition probabilities for solar density diagnostics. A brief summary of the research activity is provided
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Asian Americans with Disabilities
Asian Americans with disabilities face social stigma from Asian cultures and invisibility from the model minority myth. Along with the structural barriers related to immigrant status, these obstacles negatively impact Asian Americans’ access to disability-related services
Using Latent Profile Regression to Explore the Relationship between Religiosity and Work-related Ethical Judgments
Utilizing social structural symbolic interactionist theorizing about self-identity as presented by Weaver and Agle (2002) we obtained data related to five key measures of religiosity believed to be critical for understanding religiosity’s influence on ethical judgments. Using our five key religiosity measures we then fit a latent profile regression model to explore whether and how these constructs related to one another and to work-related ethical judgments. Results revealed that both our analytic and theoretical frameworks (latent profile regression and symbolic interactionism) were helpful in identifying religious profiles which are helpful for understanding the relationship between religiosity and work-related ethical judgments. More specifically, results indicated that extrinsic religious motivation orientation (RMO) may represent a ‘dark side’ to religiosity given higher levels of extrinsic RMO were found in a subgroup who judged unethical situations more favorably than those with lower levels of extrinsic RMO
Multicast Delivery of IPTV Over the Internet
Television represents one of the greatadvancements in information delivery. Traditionally, televisionservice has been delivered using dedicated communicationmethods such as terrestrial and satellite based wirelesstransmissions and fixed cable based transmissions. Some of thesedelivery mechanisms have advanced and now provide servicesincluding voice and Internet access. Another communicationmethod, traditional telephone service, has greatly improvedand expanded to deliver services such as television and Internetaccess.This convergence of service provides cost savings, allowingproviders to utilize existing communication networks to deliveradditional services to its customers, often at minimal or zeroinfrastructure cost. One disadvantage of this method is customerreach is still limited to those with access to dedicated serviceprovider networks. The ability to disengage television servicefrom these dedicated networks and move it to a more ubiquitousnetwork would greatly improve the customer reach of theproviders.The most obvious network choice for a delivery mediumis the Internet. Given that television delivery mechanisms havealready started the progression towards IPTV, the service isa natural fit. One issue hindering this transition is bandwidthavailability. In private delivery networks, the issue of bandwidthavailability for IPTV is often combated through the use of IPMulticasting. Considering the Internet is already believed to bebandwidth constrained, the use of multicasting could be deemeda requirement. The following paper will explore current issueswith deploying IPTV over the Internet, the use of multicast tocombat some of these problems, and the inherent challenges ofpushing multicast based IPTV services over the Internet
The steady-state repertoire of human SCF Ubiquitin ligase complexes does not require ongoing Nedd8 conjugation
The human genome encodes 69 different F-box proteins (FBPs), each of which can potentially assemble with Skp1-Cul1-RING to serve as the substrate specificity subunit of an SCF ubiquitin ligase complex. SCF activity is switched on by conjugation of the ubiquitin- like protein Nedd8 to Cul1. Cycles of Nedd8 conjugation and deconjugation acting in conjunction with the Cul1-sequestering factor Cand1 are thought to control dynamic cycles of SCF assembly and disassembly, which would enable a dynamic equilibrium between the Cul1- RING catalytic core of SCF and the cellular repertoire of FBPs. To test this hypothesis, we determined the cellular composition of SCF complexes and evaluated the impact of Nedd8 conjugation on this steady-state. At least 42 FBPs assembled with Cul1 in HEK 293 cells, and the levels of Cul1-bound FBPs varied by over two orders of magnitude. Unexpectedly, quantitative mass spectrometry revealed that blockade of Nedd8 conjugation led to a modest increase, rather than a decrease, in the overall level of most SCF complexes. We suggest that multiple mechanisms including FBP dissociation and turnover cooperate to maintain the cellular pool of SCF ubiquitin ligases
Survivorship research for people with metastatic or advanced cancer: A time for action
Over recent decades, survival outcomes for people diagnosed with cancer have changed dramatically, with approximately 20% improvement in five-year relative survival rates in high-income countries including the United States and Australia. Regardless of regions, there is a decrease in overall cancer mortality rate of about 1% per year. Likewise, the cancer disease trajectory has changed. The traditional linear cancer trajectory in which a patient moves from cancer diagnosis through to a binary outcome (cure or death)—is no longer applicable and does not adequately describe the complexity of experience for many people. Indeed, the availability of targeted therapies and immunotherapies has meant that people diagnosed with cancers once rapidly fatal in the advanced or metastatic stages, such as prostate, breast, ovarian, melanoma, myeloma, and non-small cell lung cancer, are now being treated over relatively long periods of time with treatments that slow the progression of their cancer, prolong life and control cancer symptoms.1 However, despite the ability of these novel therapies to extend life, most patients with an advanced or metastatic cancer diagnosis will never be cured. For these patients, cancer is often a chronic and complex illness that is, often unpredictable and requires ongoing monitoring, treatment, care, and support
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Waste minimization and pollution prevention awareness plan. Revision A
The purpose of this plan is to establish the Pinellas Plant Waste Minimization and Pollution Prevention Awareness Program. The plan specifies those activities and methods that will be employed to reduce the quantity and toxicity of wastes generated at the site. It is intended to satisfy the Department of Energy (DOE) and other legal requirements that are discussed in Section 1.3. A Waste Minimization Program is an organized, comprehensive, and continual effort to systematically reduce waste generation. The Waste Minimization and Pollution Prevention Awareness Program is designed to eliminate or minimize pollutant releases to all environmental media from all aspects of the site`s operations. These efforts offer increased protection of public health and the environment. Sections of this report describe: Background; Resources; Policy; Strategy, objectives, and goals; Organization and staff responsibilities; Cost accounting; Waste assessments; Waste minimization techniques; Training, awareness, and incentives; Tracking and reporting systems; Quality assurance; Information exchange and outreach; Technology transfer; Research and development; and Program evaluation
Far Ultraviolet Spectroscopic Explorer Survey of Magellanic Cloud Supernova Remnants
We report the progress to date from an ongoing unbiased ultraviolet survey of
supernova remnants in the Magellanic Clouds using the Far Ultraviolet
Spectroscopic Explorer (FUSE) satellite. This survey is obtaining spectra of a
random large sample of Magellanic Cloud supernova remnants with a broad range
of radio, optical, and X-ray properties. To date, 39 objects have been observed
in the survey (38 in the LMC and one in the SMC) and 15 have been detected, a
detection rate of nearly 40%. Our survey has nearly tripled the number of
UV-detected SNRs in the Magellanic Clouds (from 8 to 22). Because of the
diffuse source sensitivity of FUSE, upper limits on non-detected objects are
quite sensitive in many cases. Estimated total luminosities in O~VI span a
broad range from considerably brighter to many times fainter than the inferred
soft X-ray luminosities, indicating that O~VI can be an important and largely
unrecognized coolant in certain objects. We compare the optical and X-ray
properties of the detected and non-detected objects but do not find a simple
indicator for ultraviolet detectability. Non-detections may be due to
clumpiness of the emission, high foreground extinction, slow shocks whose
emission gets attenuated by the Magellanic interstellar medium, or a
combination of these effects.Comment: 34 pages, 26 figures in 8 separate JPG figure files; the
characteristics of individual detected supernova remnants are summarized in
an Appendi
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