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North Slope Borough water study: a background for planning

The Planning and Research Section of Alaska Dept. of Natural Resources initiated this pilot water study with the North Slope Borough and the University of Alaska's Arctic Environmental Information and Data Center and Institute of Water Resources. Traditional and present water uses in the eight North Slope Borough villages are examined to assist in evaluating and planning for present and future water use, treatment, and disposal requirements.Prepared for Alaska Department of Natural Resources Planning and Research Sectio

Remote Monitoring of Implantable Cardioverter Defibrillator

The rate of implantable cardioverter defibrillator (ICD) implantation has gone up as primary and secondary prevention trials have relatively consistently shown significant improvement in mortality and morbidity. Most patients with ICDs are followed routinely at intervals ranging from 3 to 6 months. Many patients require additional non-scheduled visits to investigate symptoms that may or may not relate to their cardiac disease or device. Appropriate and inappropriate therapies of implantable cardioverter defibrillators have a major impact on morbidity and quality of life in ICD recipients. Remote monitoring systems can substitute for routine follow-up visits and/ or deliver continuous diagnostic and device status information. Remote monitoring of ICDs can decrease the need for many patient visits and, thereby, probably reduce expense

Mass transfer between single bubbles and Newtonian and non-Newtonian liquids

Instantaneous values of bubble volume, shape, rise velocity, overall mass transfer product, surface area and overall mass transfer coefficient for single carbon dioxide bubbles in free rise through liquids contained in a 10.16 cm I.D. column were experimentally evaluated.In the experimental investigations, a novel data processing technique was used which allowed accurate measurement of the instantaneous rate of change of pressure of the constant volume system, consisting of a liquid contained in the mass transfer column and isolated from the atmosphere, as a bubble rose through the liquid and dissolved in it.A wide range of bubble sizes (0.2 - 6.0 cm diameter) was investigated in three Newtonian liquids - distilled water and two aqueous Glycerol solutions - and a non-Newtonian viscoelastic aqueous Polyox solution, which exhibited pseudoplastic behaviour in steady shear. Detailed comparisons of the collected data with existing theoretical models relating to bubble rise velocity and overall mass transfer coefficient were carried out.In the carbon dioxide-distilled water system, bubble shape was seen to go from spherical to oblate spheroidal to spherical cap with increasing bubble size. Bubble shapes observed in the two aqueous Glycerol solutions were similar to those observed in water, with an additional > hemisphere shape and the occurrence of spherical cap bubble skirting in the more concentrated Glycerol solution.The shapes and terminal rise velocities of large bubbles in the Newtonian liquids were found to be influenced by the proximity of the column walls. The terminal rise velocity data for bubbles in the non-Newtonian Polyox solution was lower than for distilled water; and exhibited an abrupt increase by a factor in excess of 4 at a critical bubble size. Bubbles in the Polyox solution exhibited tailing over the size range 0.27 cm ≤ Dₑ < 2.2 cm. Bubble tailing is known to be peculiar to non -Newtonian fluid fields. In the Polyox solution suitable bubble sizes adopted spherical, prolate spheroidal, oblate spheroidal and spherical cap shapes. A previously unreported spherical cap bubble rear configuration was observed for large bubbles in the Polyox solution.Instantaneous overall mass transfer coefficients based on actual bubble surface areas were evaluated. The transfer coefficients of small bubbles in all four solutions investigated were closely predicted by theoretical equations for circulating spheres and for rigid spheres in creeping flow. The transfer coefficient data for carbon dioxide bubbles in the Polyox solution confirmed the suggestion (A7) that at the critical bubble size in viscoelastic pseudoplastic liquids a transfer from rigid to circulating body behaviour in creeping flow occurred. Certain bubble shape transitions were found to result in maxima in the transfer coefficient versus diameter plots for the solutions investigated

Modeling in the Stateflow(Registered Trademark) Environment to Support Launch Vehicle Verification Testing for Mission and Fault Management Algorithms in the NASA Space Launch System

No abstract availabl

Shear Detection of Microencapsulated Cells for Monoclonal Antibody Production Scaleup

Scale the reported hydrodynamic shear values in industrial bioreactors for monoclonal antibody production to the shear stress measured in our custom microneedle prototype by extruding microencapsulated CHO cells. A correlation between the number of extrusion loops to reduction in cell viability enables a scalable screening method for bioprocessing efficiency

Measuring Latinos' Perceptions of Depression: A Confirmatory Factor Analysis of the Illness Perception Questionnaire

This study examined the psychometric properties of the Revised Illness Perception Questionnaire adapted for a clinical sample of low-income Latinos suffering from depression. Participants (N = 339) were recruited from public primary care centers. Their average age was 49.73 years and the majority was foreign born females of either Mexican or Central American descent. Confirmatory factor analysis was used to test the factor structure of this measure. Construct and discriminant validity and internal consistency were evaluated. After the elimination of three items because of low factor loadings (< .40) and the specification of seven error covariances, a revised model composed of 24 items had adequate goodness-of-fit indices and factor loadings, supporting construct validity. Each of the subscales reported satisfactory internal consistency. Intercorrelations between the 5 illness perception factors provided initial support for the discriminant validity of these factors in the context of depression. The establishment of the psychometric properties of this adapted measure will pave the way for future studies examining the role illness perceptions play in the help seeking and management of depression among Latinos

IELE: An Intermediate-Level Blockchain Language Designed and Implemented Using Formal Semantics

Most languages are given an informal semantics until they are implemented, so the formal semantics comes later. Consequently, there are usually inconsistencies among the informal semantics, the implementation, and the formal semantics. IELE is an LLVM-like language for the blockchain that was specified formally and its implementation, a virtual machine, generated from the formal specification. Moreover, its design was based on problems observed formalizing the semantics of the Ethereum Virtual Machine (EVM) and from formally specifying and verifying EVM programs (also called “smart contracts”), so even the design decisions made for IELE are based on formal specifications. A compiler from Solidity, the predominant high-level language for smart contracts, to IELE has also been implemented, so Ethereum contracts can now also be executed on IELE. The virtual machine automatically generated from the semantics of IELE is shown to be competitive in terms of performance with the state of the art and hence can stand as the de facto implementation of the language in a production setting. Indeed, IOHK, a major blockchain company, is currently experimenting with the IELE VM in order to deploy it as its computational layer in a few months. This makes IELE the first practical language that is designed and implemented as a formal specification. It took only 10 man-months to develop IELE, which demonstrates that the programming language semantics field has reached a level of maturity that makes it appealing over the traditional, adhoc approach even for pragmatic reasons.Ope

Progress Implementing a Model-Based Iterative Reconstruction Algorithm for Ultrasound Imaging of Thick Concrete

All commercial nuclear power plants (NPPs) in the United States contain concrete structures. Typical concrete structures in these plants can be grouped into four general categories: primary containment buildings, containment internal structures, secondary containments/reactor buildings, and other structures, such as spent fuel pools and cooling towers. These structures provide important foundation, support, shielding, and containment functions. Identification and management of aging and degradation of concrete structures is fundamental to the proposed long-term operation of NPPs. Consequently, imaging techniques for a quantitative assessment of any safety issues related to plant aging and the acceptability of concrete structures is necessary in order to avoid premature decommission of NPPs. Imaging of thick concrete is a challenging endeavor. Unlike most metallic materials, reinforced concrete is a nonhomogeneous material, a composite with a low-density matrix, a mixture of cement, sand, aggregate and water, and a high-density reinforcement, made up of steel rebar or tendons. Concrete structures in NPPs are often inaccessible and contain large volumes of massively thick concrete. While acoustic imaging using synthetic aperture focusing technique (SAFT) works adequately well for thin specimens of concrete such as concrete transportation structures, enhancements are needed for heavily reinforced, thick concrete. We argue that image reconstruction quality for acoustic imaging in thick concrete could be improved with Model-Based Iterative Reconstruction (MBIR) techniques. MBIR is a powerful technique for solving inverse problems. MBIR works by designing a probabilistic model for the measurements (forward model) and a probabilistic model for the object (prior model). Both models are used to formulate an objective function (cost function), such as the maximum a posteriori (MAP) cost function. The final step in MBIR is to optimize the cost function. While more accurate models produce high quality solutions, they make the cost function more complicated. This in return makes solving the inverse problem very computationally expensive. For our application, MBIR will iterate until it finds the intensity reflectivity coefficients (IRC) for every voxel on the field of view that optimize the cost function. Previously, we have demonstrated a first implementation of MBIR for an ultrasonic transducer array system. The original forward model has been upgraded to account for direct arrival signal, which greatly contributes to reconstruction artifacts in particular for one-sided reconstruction. This upgrade is successfully able to cancel out the effect of the direct arrival signal on the reconstruction. Updates to the forward model will be documented and the new algorithm will be assessed with synthetic and empirical samples