Performance of Steel Pipelines Backfilled with Controlled Low-Strength Material (CLSM) under Seismic Wave Propagation and Reverse-Slip Fault Rupture

Title from PDF on title page viewed May 18, 2020Dissertation advisor: Ceki HalmenVitaIncludes bibliographical references (pages 120-124)Thesis (Ph.D.)--School of Computing and Engineering and Department of Geosciences. University of Missouri--Kansas City, 2019Seismic events may drastically damage buried pipelines affecting economy and public safety. Traditionally, buried pipelines are bedded and backfilled with compacted soils, which is labor intensive, time consuming, and could be a safety hazard to workers. Many studies have shown that achieving a proper compaction level around pipelines can be a difficult task. Improper compaction can greatly reduce performance of the pipelines under loads. Controlled Low-Strength Materials (CLSM) is a group of cementitious materials that can be used as an alternative to compacted soils to backfill pipelines. These mixtures are highly flowable in their fresh state and are solid in the final state providing a uniform support around pipelines. Although there is considerable research about the advantages of using CLSM to backfill pipelines from construction point of view, there is no research on the performance of pipelines embedded in CLSM subject to seismic loads. In this research, 3D FEA was conducted using ABAQUS software to determine the performance of buried steel pipes backfilled with CLSM when subjected to seismic wave propagation and reverse-slip fault rupture. Under seismic wave propagation, the study started by evaluating the ASCE guidelines and its design limitations. Then, several FE model parameters were evaluated for their effects on FE model results. After setting the model parameters to match the predicted stresses by the ASCE guidelines, the developed FE model was used to evaluate the pipe seismic performance with various soil and CLSM backfill materials. Both linear and non-linear material behavior were considered in this study. Under seismic fault rupture, the study developed a 3D FE model matching results from a full-scale testing performed by others. Various FE model parameters were also evaluated. Then, the developed FE model was utilized to determine the pipe seismic performance of CLSM mixture compared to compacted soil backfill. Results indicated that for 3D FEA pipe seismic analysis, FE model parameters can have a significant effect on the results. In addition, with a proper design buried steel pipe embedded in CLSM backfill with all its inherent advantages can perform as well as or better than soils in seismic prone areas.Introduction -- Literature review -- Buried pipelines subject to seismic wave propagation -- Buried pipelines subject to reverse-slip fault rupture -- Summar

Guidelines for a Roadway Management System (RMS) for Local Governments

The objective of the proposed guidelines for a roadway management system (RMS) is to describe a framework for a modular and user-friendly RMS that will assist local government agencies of all sizes in coordinating and planning routine and preventive maintenance, rehabilitation, and reconstruction. These guidelines include a step-by-step procedure to establish a customized RMS for local government agencies. The resulting RMS, based upon the proposed guidelines, will be a systematic methodology that can assist local government agencies to evaluate the current pavement condition, identify problems on the pavements, select the best repair and maintenance strategies with the minimum cost, and generate a schedule and priority program for these actions at both project and network levels at both the present time and the future. The terms and definitions used in the inventory program, the referencing and the defining methods for the roadway network, and the understanding between the project and the network level are established, such that the data collection process can be initiated to gather information from concerned pavements within the roadway network. A step-by-step procedure is described for obtaining the pavement condition as represented by the pavement condition index (PCI) value for different low-volume flexible and built-up pavement types as well as different maintenance strategies. In the proposed guidelines, the PCI value forms the basis for establishing the other components as well as developing the coordination among the components of an RMS. Methods to generate the maintenance, rehabilitation, and reconstruction actions based upon the PCI are established. A pavement performance prediction model is developed to forecast the future PCI value, and a methodology for life cycle cost analysis is also provided in these guidelines. Finally, these guidelines briefly demonstrate the tasks that should be considered and included in reports to elected boards or councils that approve the funds regarding local government agencies\u27 needs

Mechanisms of the action of povidone-iodine against human and avian influenza A viruses: its effects on hemagglutination and sialidase activities

<p>Abstract</p> <p>Background</p> <p>Influenza virus infection causes significant morbidity and mortality and has marked social and economic impacts throughout the world. The influenza surface glycoproteins, hemagglutinin (HA) and neuraminidase (NA), act cooperatively to support efficient influenza A virus replication and provide the most important targets for anti-influenza chemotherapy. In this study, povidone-iodine (PVP-I), which has a broad-spectrum microbicidal property, was examined for its inhibitory effects against influenza virus infection in MDCK cells and the mechanisms of PVP-I action on HA and NA were revealed.</p> <p>Results</p> <p>Results obtained using a novel fluorescence- and chromogenic-based plaque inhibition assay showed that 1.56 mg/ml PVP-I inhibited infections in MDCK cells of human (8 strains) and avian (5 strains) influenza A viruses, including H1N1, H3N2, H5N3 and H9N2, from 23.0–97.5%. A sialidase inhibition assay revealed that PVP-I inhibited N1, N2 and N3 neuraminidases with IC₅₀values of 9.5–212.1 μg/ml by a mixed-type inhibition mechanism. Receptor binding inhibition and hemagglutinin inhibition assays indicated that PVP-I affected viral hemagglutinin rather than host-specific sialic acid receptors.</p> <p>Conclusion</p> <p>Mechanisms of reduction of viral growth in MDCK cells by PVP-I involve blockade of viral attachment to cellular receptors and inhibition of viral release and spread from infected cells. Therefore, PVP-I is useful to prevent infection and limit spread of human and avian influenza viruses.</p

Comparative genome analysis between Southeast Asian and South American Zika viruses

Objective: To understand the cause for the differences between potentially mild Southeast Asian and the more pathogenic ZIKV in South America. Methods: A comparative genomic analysis was performed to determine putative causations stemming from ZIKV. Results: Phylogenetic analyses integrating geographical and time factors revealed that Southeast Asian ZIKV might not be the direct source of South American outbreaks as previously speculated. Amino acid residues unique to South American ZIKV isolates at the envelope, pr and NS1 proteins are listed and shown in the structural context. These unique residues on external viral proteins are not found in Southeast Asian ZIKV and could be responsible for the ongoing outbreak either via an intrinsic property of the virus or interactions with human immunity. Only a selected few primer/probe sets currently in clinical use were identified of being capable of detecting ZIKV strains worldwide. The envelope proteins of dengue virus (DENV) and ZIKV also showed a remarkable degree of similarity especially at the surface residues. Conclusions: These findings may help explain the cross-reactivity of DENV antibodies to ZIKV. Thus, major caveats must be exercised in using existing diagnostic tools for ZIKV

A Genetically Hard-Wired Metabolic Transcriptome in Plasmodium falciparum Fails to Mount Protective Responses to Lethal Antifolates

Genome sequences of Plasmodium falciparum allow for global analysis of drug responses to antimalarial agents. It was of interest to learn how DNA microarrays may be used to study drug action in malaria parasites. In one large, tightly controlled study involving 123 microarray hybridizations between cDNA from isogenic drug-sensitive and drug-resistant parasites, a lethal antifolate (WR99210) failed to over-produce RNA for the genetically proven principal target, dihydrofolate reductase-thymidylate synthase (DHFR-TS). This transcriptional rigidity carried over to metabolically related RNA encoding folate and pyrimidine biosynthesis, as well as to the rest of the parasite genome. No genes were reproducibly up-regulated by more than 2-fold until 24 h after initial drug exposure, even though clonal viability decreased by 50% within 6 h. We predicted and showed that while the parasites do not mount protective transcriptional responses to antifolates in real time, P. falciparum cells transfected with human DHFR gene, and adapted to long-term WR99210 exposure, adjusted the hard-wired transcriptome itself to thrive in the presence of the drug. A system-wide incapacity for changing RNA levels in response to specific metabolic perturbations may contribute to selective vulnerabilities of Plasmodium falciparum to lethal antimetabolites. In addition, such regulation affects how DNA microarrays are used to understand the mode of action of antimetabolites

Etude comparative de paramètres agrophysiologiques liés à la production chez le cotonnier G. hirsutum L. et analyse de leur déterminisme génétique

Le cotonnier G. hirsutum est une plante à croissance indéterminée, la phase de fructification n'étant pas séparée de la phase de croissance végétative. Le développement végétatif dépend de la capacité de la plante à retenir ses capsules sur les sites fructifères. Le taux de rétention de capsules dépend à la fois de facteurs environnementaux (trophiques, climatiques, stress biotiques ou abiotiques) et génétiques (variétés), qui rendent la sélection sur le critère productivité relativement délicate. Aujourd'hui, l'installation de la production sur la plante peut être suivie pendant la croissance ou en fin de cycle, par des techniques nouvelles d' analyse («Plant Mapping»). L'objet de ce travail a été d'utiliser ces techniques pour décrire la variabilité d'une collection de six variétés et identifier des prédicteurs du rendement. Les combinaisons de ces six parents ont été réalisées selon un plan diallèle pour étudier l'héritabilité des nouveaux paramètres identifiés. Il est apparu que les positions 1 et 2 sur l'ensemble des sixième à dixième branches fructifères, constituaient des sites importants pour permettre au sélectionneur de juger du potentiel productif d'une variété ou d'une plante dans la descendance d'un croisement. La production portée sur les branches végétatives, apparaît également comme un critère de sélection en corrélation négative avec la productivité. L'analyse génétique a montré que ces trois paramètres possèdent une bonne héritabilité. L'existence chez le cotonnier, d'une variabilité phénotypique élevée sur ces paramètres, permet d'espérer des gains génétiques notables au niveau de la création de lignées. (Résumé d'auteur

The Relationships Between Police Performance and Public Confidence: A Case Study in Thailand

There have been very few empirical studies conducted in Thailand on public confidence in the Thai police. Most studies on this topic in Thailand are descriptive and have been done only as part of the organization’s annual reports. The results of this study were from a national survey of 9900 Thai people. The study examined the correlations between various factors and public attitudes toward their confidence in police. Of the four categories (demographic, contextual, contact with the police, and attitudes toward police performance), the study’s findings revealed the attitudes toward crime suppression and toward crime prevention, in that order, had the strongest correlations with confidence attitudes in police