2,490 research outputs found
Landslide Stabilization at Missouri Route K Bridge over Blackwater River
In May 2002, a landslide on the south bank of the Blackwater River damaged the Missouri Route K bridge that crosses it. A flood on the river triggered the landslide. Based on the field investigation and stability back-analysis, it appeared that the landslide actually consisted of two separate slides – a shallow slide triggered by rapid drawdown of the river and a deep slide triggered by artesian water pressures in a subsurface gravel layer. A rock berm that was keyed into the gravel was constructed to stabilize the slope. The rock toe berm was designed to resist both the shallow and deep slide by providing weight to the slope to prevent a rapid drawdown failure and providing a drainage outlet to relieve artesian pressures in the gravel layer
Soil Property Determination for a Seismic Study
Static and dynamic soil property data were needed for input into the seismic retrofit design for the I-155 Mississippi River crossing located near the center of the New Madrid Seismic Zone. Soils consisted of recent river alluvium underlain by very dense soils of the Mississippi embayment. The field investigation consisted of conventional borings, downhole geophysical tests to measure shear wave velocity, and seismic piezo-cone soundings. SPT energy measurements were made at one boring to confirm hammer energy for liquefaction evaluation. This paper summarizes the data and provides site specific correlation of shear wave velocity vs. N-value from the seismic cone and downhole geophysical tests; measured SPT energy value; and estimates of static and dynamic soil properties
Initial Survey of Engineering Technology Capstone Courses and TeamworkBuilding Using CATME
This paper represents a first step in what is to become a multi –institutional initiative focused on identifying best practices for developing and improving teamwork skills within the Capstone experiences of engineering, technology and computing programs. Teamwork in this paper is defined and measured as the dimensions measured by the CATME Peer Review [1], which is currently used by thousands of technology and engineering instructors and institutions worldwide. The CATME Peer Review measurement tool is used to collect self and peer evaluations of team members’ contributions on five different teamwork dimensions [2]. These teamwork dimensions are 1) pose the knowledge, skills, and abilities to help the team; 2) expect quality work from the team; 3) keep the team on schedule; 4) positive interactions between teammates to help the team; and 5) all team members contribute to the team\u27s work and success. Pung and Farris[3] used CATME in a one semester junior level design class and reported a “significant improvement” in student behavior when compared to the old system of peer review. A workshop was developed to assemble all the participants, and develop a systematic method of evaluating teamwork building using CATME. All the participating schools and faculty will be testing changes in their Capstone courses and sharing the results of this analysis, in teamwork skills, with their colleagues
Refining Lucy Mission Delta-V During Spacecraft Design Using Trajectory Optimization Within High-Fidelity Monte Carlo Maneuver Analysis
Recent advances linking medium-fidelity trajectory optimization and high-fidelity trajectory propagation/maneuver design software with Monte Carlo maneuver analysis and parallel processing enabled realistic statistical delta-V estimation well before launch. Completing this high-confidence, refined statistical maneuver analysis early enabled release of excess delta-V margin for increased dry mass margin for the Lucy Jupiter Trojan flyby mission. By 3.3 years before launch, 16 of 34 TCMs had 1000 re-optimized trajectory design samples, yielding tens of m/s lower 99%-probability delta-V versus targeting maneuvers to one optimal trajectory. One year later, 1000 re-optimized samples of all deterministic maneuvers and subsequent flybys further lowered estimated delta-V
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Discovery of a mammalian splice variant of myostatin that stimulates myogenesis
Myostatin plays a fundamental role in regulating the size of skeletal muscles. To date, only a single myostatin gene and no splice variants have been identified in mammals. Here we describe the splicing of a cryptic intron that removes the coding sequence for the receptor binding moiety of sheep myostatin. The deduced polypeptide sequence of the myostatin splice variant (MSV) contains a 256 amino acid N-terminal domain, which is common to myostatin, and a unique C-terminus of 65 amino acids. Western immunoblotting demonstrated that MSV mRNA is translated into protein, which is present in skeletal muscles. To determine the biological role of MSV, we developed an MSV over-expressing C2C12 myoblast line and showed that it proliferated faster than that of the control line in association with an increased abundance of the CDK2/Cyclin E complex in the nucleus. Recombinant protein made for the novel C-terminus of MSV also stimulated myoblast proliferation and bound to myostatin with high affinity as determined by surface plasmon resonance assay. Therefore, we postulated that MSV functions as a binding protein and antagonist of myostatin. Consistent with our postulate, myostatin protein was
co-immunoprecipitated from skeletal muscle extracts with an MSV-specific antibody. MSV over-expression in C2C12 myoblasts blocked myostatin-induced Smad2/3-dependent signaling, thereby confirming that MSV antagonizes the
canonical myostatin pathway. Furthermore, MSV over expression increased the abundance of MyoD, Myogenin and MRF4 proteins (P,0.05), which indicates that MSV stimulates myogenesis through the induction of myogenic regulatory factors. To help elucidate a possible role in vivo, we observed that MSV protein was more abundant during early post-natal muscle development, while myostatin remained unchanged, which suggests that MSV may promote the growth of skeletal muscles. We conclude that MSV represents a unique example of intra-genic regulation in which a splice variant directly antagonizes the biological activity of the canonical gene product
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Adaptive awareness for personal and small group decision making.
Many situations call for the use of sensors monitoring physiological and environmental data. In order to use the large amounts of sensor data to affect decision making, we are coupling heterogeneous sensors with small, light-weight processors, other powerful computers, wireless communications, and embedded intelligent software. The result is an adaptive awareness and warning tool, which provides both situation awareness and personal awareness to individuals and teams. Central to this tool is a sensor-independent architecture, which combines both software agents and a reusable core software framework that manages the available hardware resources and provides services to the agents. Agents can recognize cues from the data, warn humans about situations, and act as decision-making aids. Within the agents, self-organizing maps (SOMs) are used to process physiological data in order to provide personal awareness. We have employed a novel clustering algorithm to train the SOM to discern individual body states and activities. This awareness tool has broad applicability to emergency teams, military squads, military medics, individual exercise and fitness monitoring, health monitoring for sick and elderly persons, and environmental monitoring in public places. This report discusses our hardware decisions, software framework, and a pilot awareness tool, which has been developed at Sandia National Laboratories
Healthcare disparities for women hospitalised with myocardial infarction and angina
Ischaemic heart disease persists as the leading global cause of death. Myocardial infarction (MI) accounts for a large proportion of death due to cardiovascular disease. Between 2007 and 2016, age-sex standardised mortality for MI in Scotland has fallen by 42.5% from 129 to 74 per 100,000 population – a trend also apparent in other countries. Despite improvements in survival, considerable disparities exist according to sexin terms of delivery of guideline-recommended treatments and outcomes following MI suggesting women may be disadvantaged. Use of high-sensitivity troponin assays with sex-specific thresholds increases the detection of MI in women. However, women are less likely to undergo percutaneous coronary revascularisation (PCI) and are more often subject to underutilisation of evidence-based secondary preventative pharmacotherapy. Differences in adoption of invasive management may, in part, be explained by a perception held by clinicians and patients that outcomes are worse for women receiving PCI, as well as differences in symptoms and baseline risk profile which may impact clinical decision-making. Adverse events post-MI, including cardiogenic shock, heart failure and death, remain more common in women than in men, most notably in those with ST-elevation myocardial infarction (STEMI). Whether sex remains an independent predictor of adverse events despite adjustments for the higher risk-profile of women, notably age, is less clear. We hypothesised that sex-related differences in demographics and comorbidity underpin disparities in management and outcomes of women and men hospitalised with MI or angina. We investigated this hypothesis by analysis of a contemporary secondary care electronic registry (e-Registry) using electronic patient records (EPRs) for patients admitted to a complex regional healthcare network.PostprintPeer reviewe
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