Improvement of Soil and Rock Properties for Foundation Support for Missouri Interchange Project

Expansion and growth in the southwestern region of Missouri necessitated the expansion of State Route 249 and the construction of a new interchange to provide service to the Joplin, Missouri area. The project is located above a former lead and zinc mine in Jasper County, Missouri and includes a five bridge interchange connecting State Route 249 and US Route 171. The variable subsurface conditions, both natural and manmade prompted the design team to use ground improvement via grouting and small diameter micropiles to provide support for several of the bridge foundations on the project. The scope of work included mine shaft closures, 17,070 m (56,000 ft) of overburden and rock drilling, 3,400 m (11,155 ft) of micropiles, 400 m³ (524 cy) of balanced/stabilized high mobility grouts, and over 6,800 m³ (8,900 cy) of low mobility grout. The selection of the grout used was based on the actual subsurface conditions. Low mobility grout (LMG) was used in voided conditions and for closure of the mine shafts encountered during the excavation. High mobility grout (HMG) was used in fractured rock with the goal of improving the mechanical properties of the rock underneath the future bridge footings and controlling grout volumes during micropile installation. The split spacing method was utilized for both LMG and HMG holes. Geology of the project consisted of extremely variable bedrock with strong to very strong limestone, chert, breccia, extremely weak shale, and weak to strong sandstone in conjunction with the activities associated with the mining disturbance (such as partial filled vertical mine shafts, shallow and deep mine horizons, modified hydrology including artesian conditions). Real time monitoring and recording of all drilling and grouting parameters was conducted to assist in the evaluation of in-situ geological properties of the site in order to modify the ground improvement and micropile program as necessary. This paper will discuss the design and execution of the ground improvement and micropile program. The project is an excellent example of the use of multiple ground improvement and foundation support techniques combined with real time data analysis to provide a foundation support solution for a complex geological environment

Als3 is a Candida albicans invasin that binds to cadherins and induces endocytosis by host cells.

Candida albicans is the most common cause of hematogenously disseminated and oropharyngeal candidiasis. Both of these diseases are characterized by fungal invasion of host cells. Previously, we have found that C. albicans hyphae invade endothelial cells and oral epithelial cells in vitro by inducing their own endocytosis. Therefore, we set out to identify the fungal surface protein and host cell receptors that mediate this process. We found that the C. albicans Als3 is required for the organism to be endocytosed by human umbilical vein endothelial cells and two different human oral epithelial lines. Affinity purification experiments with wild-type and an als3delta/als3delta mutant strain of C. albicans demonstrated that Als3 was required for C. albicans to bind to multiple host cell surface proteins, including N-cadherin on endothelial cells and E-cadherin on oral epithelial cells. Furthermore, latex beads coated with the recombinant N-terminal portion of Als3 were endocytosed by Chinese hamster ovary cells expressing human N-cadherin or E-cadherin, whereas control beads coated with bovine serum albumin were not. Molecular modeling of the interactions of the N-terminal region of Als3 with the ectodomains of N-cadherin and E-cadherin indicated that the binding parameters of Als3 to either cadherin are similar to those of cadherin-cadherin binding. Therefore, Als3 is a fungal invasin that mimics host cell cadherins and induces endocytosis by binding to N-cadherin on endothelial cells and E-cadherin on oral epithelial cells. These results uncover the first known fungal invasin and provide evidence that C. albicans Als3 is a molecular mimic of human cadherins

Assessing the Likelihood of Rare Medical Events in Astronauts

Despite over half a century of manned space flight, the space flight community is only now coming to fully assess the short and long term medical dangers of exposure to reduced gravity environments. Further, as new manned spacecraft are designed and with the advent of commercial flight capabilities to the general public, a full understanding of medical risk becomes even more critical for maintaining and understanding mission safety and crew health. To address these critical issues, the National Aeronautics and Space Administration (NASA) Human Research Program (HRP) has begun to address the medical hazards with a formalized risk management approach by effectively identifying and attempting to mitigate acute and chronic medical risks to manned space flight. This paper describes NASA Glenn Research Center?s (GRC) efforts to develop a systematic methodology to assess the likelihood of in-flight medical conditions. Using a probabilistic approach, medical risks are assessed using well established and accepted biomedical and human performance models in combination with fundamentally observed data that defines the astronauts? physical conditions, environment and activity levels. Two different examples of space flight risk are used to show the versatility of our approach and how it successfully integrates disparate information to provide HRP decision makers with a valuable source of information which is otherwise lacking

Upscaling key ecosystem functions across the conterminous United States by a water-centric ecosystem model

We developed a water-centric monthly scale simulation model (WaSSI-C) by integrating empirical water and carbon flux measurements from the FLUXNET network and an existing water supply and demand accounting model (WaSSI). The WaSSI-C model was evaluated with basin-scale evapotranspiration (ET), gross ecosystem productivity (GEP), and net ecosystem exchange (NEE) estimates by multiple independent methods across 2103 eight-digit Hydrologic Unit Code watersheds in the conterminous United States from 2001 to 2006. Our results indicate that WaSSI-C captured the spatial and temporal variability and the effects of large droughts on key ecosystem fluxes. Our modeled mean (±standard deviation in space) ET (556 ± 228 mm yr−1) compared well to Moderate Resolution Imaging Spectroradiometer (MODIS) based (527 ± 251 mm yr−1) and watershed water balance based ET (571 ± 242 mm yr−1). Our mean annual GEP estimates (1362 ± 688 g C m−2 yr−1) compared well (R2 = 0.83) to estimates (1194 ± 649 g C m−2 yr−1) by eddy flux-based EC-MOD model, but both methods led significantly higher (25–30%) values than the standard MODIS product (904 ± 467 g C m−2 yr−1). Among the 18 water resource regions, the southeast ranked the highest in terms of its water yield and carbon sequestration capacity. When all ecosystems were considered, the mean NEE (−353 ± 298 g C m−2 yr−1) predicted by this study was 60% higher than EC-MOD\u27s estimate (−220 ± 225 g C m−2 yr−1) in absolute magnitude, suggesting overall high uncertainty in quantifying NEE at a large scale. Our water-centric model offers a new tool for examining the trade-offs between regional water and carbon resources under a changing environment

The Fontan operation in infants less than 2 years of age

AbstractYoung age remains a reported risk factor for a successful Fontan operation despite improved survival rates. Since March 1978, the Fontan operation has been performed in 47 patients. To avoid a primary or secondary polliative shunt, an early Fontan procedure (Group 1: mean age 1.5 ± 0.5 years, range 0.6 to 2) has been performed in 17 children with the outcome similar to that of the remaining 30 older patients (Group 2: mean age 7.5 ± 5 years, range 2.4 to 23 years). Preoperatively both groups had acceptable hemodynamic status for a successful Fontan result.Operative variables including cardiopulmonary bypass time, aortic cross-clamp time and core temperature were similar between groups and did not affect mortality. The postoperative mortality rate including early surgical (0% vs. 13%, respectively), late (18% vs. 12%) and total (18% vs. 23%) was similar between Groups 1 and 2 (p > 0.05). Immediate postoperative arrhythmias were more frequent in Group 1 (71% vs. 25%, p < 0.01) with no related mortality, while late arrhythmias occurred with equal frequency (29% vs. 39%, p > 0.05). Group 1 infants required a longer hospital stay (22 ± 9 vs. 14 ± 5 days, p < 0.01).Thus, young age is not a risk factor for successful outcome of the Fontan operation in patients with acceptable preoperative hemodynamic status. An early Fontan operation may also avoid prolonged palliative procedures and their potential deleterious effects

A general few-projection method for tomographic reconstruction of samples consisting of several distinct materials

We present a method for tomographic reconstruction of objects containing several distinct materials, which is capable of accurately reconstructing a sample from vastly fewer angular projections than required by conventional algorithms. The algorithm is more general than many previous discrete tomography methods, as: (i) a priori knowledge of the exact number of materials is not required; (ii) the linear attenuation coefficient of each constituent material may assume a small range of a priori unknown values. We present reconstructions from an experimental x-ray computed tomography scan of cortical bone acquired at the SPring-8 synchrotron

Estimated Probabililty of Chest Injury During an International Space Station Mission

The Integrated Medical Model (IMM) is a decision support tool that is useful to spaceflight mission planners and medical system designers when assessing risks and optimizing medical systems. The IMM project maintains a database of medical conditions that could occur during a spaceflight. The IMM project is in the process of assigning an incidence rate, the associated functional impairment, and a best and a worst case end state for each condition. The purpose of this work was to develop the IMM Chest Injury Module (CIM). The CIM calculates the incidence rate of chest injury per person-year of spaceflight on the International Space Station (ISS). The CIM was built so that the probability of chest injury during one year on ISS could be predicted. These results will be incorporated into the IMM Chest Injury Clinical Finding Form and used within the parent IMM model