44 research outputs found
On the Extended Forms of Phenomenological Models for the Lattice Dynamics of BCC Transition Metals
No full textThe Sharma-Joshi and Krebs phenomenological models for the lattice dynamics of cubic metals have been extended and are applied to study the phonon dispersion curves of tungsten, a metal for whlch long range forces are also important. It has been found that, unlike extended forms of the de Launay model (Shukla and Cavalheiro 1973a) for certain cubic metals, the models studied here for b.c.c. transition metals are not always adequate. Possible reasons for the shortcomings of the results are pointed out and discussed. The role of angular forces, particularly when they are used along with a fairly good conduction electron-ion interaction term, has been examined and found to be unimportant</jats:p
Top-ten most-cited articles on anterior column release in the context of minimally invasive lumbar interbody fusion
No full textIntroduction: Lateral anterior column release (ACR) is a minimally invasive option for the correction of sagittal plane deformity. To assemble a homogeneous picture of published research on ACR, an advanced bibliometric analysis was conducted to compile the top-ten most-cited articles on the topic of ACR.
Methods: A keyword search using the Thomson Reuters Web of Knowledge was conducted to identify articles discussing the role of lateral ACR. The articles were then ranked based on the total number of citations to identify the ten most-cited articles published. A subjective appraisal of the findings of these articles was conducted to provide a ranked literature review and to examine trends in the study of ACR between 2012 and 2019.
Results: The earliest published article on ACR was in 2012 by Deukmedjian et al. Three articles were in vitro biomechanical assessments of ACR, and seven articles were on outcome analyses, which were either case series or case controlled. The most-cited article was a biomechanical study authored by Uribe et al. The article with the highest rate of citations/year was authored by Manwaring et al. Uribe and the European Spine Journal were the most frequently cited author and journal, respectively.
Conclusions: The lateral ACR approach has enjoyed significant scholarly attention since its advent. Higher-level analyses with robust control groups, larger sample sizes, and long-term follow-up are necessary to improve our understanding of this approach
Electrical and dielectric properties of PVdF-HFP – PMMA – (PC + DEC)- LiClO4 based gel polymer electrolyte
No full textQuantifying effects of temporal regression techniques on resting state fMRI parameters in patients with brain tumor
No full textResting state functional magnetic resonance imaging (rs-fMRI) employs blood oxygen level dependent (BOLD) signals as an indirect measure of the brain's intrinsic neuronal activities. Studies in the healthy control (HC) population have revealed that temporal regression techniques utilizing cerebrospinal fluid (CSF) and white matter (WM) signals as covariates are being used to enhance the signal to noise ratio (SNR) of BOLD signals. However, in brain tumor data, tumors may cause alteration in boundaries of brain tissues such as CSF, WM, and gray matter (GM). This could lead to covariates in CSF and WM signals representing GM signals and vice versa. The goal of this study is to undertake a quantitative investigation of resting state fMRI temporal regression techniques and their influence on local and global resting state parameters in patients with brain tumor. The current work evaluates changes in resting state parameters as a result of several temporal regression approaches in brain tumor patients and healthy control (HC) populations. Five different temporal regression strategies including motion parameters, motion scrubbing, and physiological noise regressors were implemented. We investigated the influence of those temporal regression techniques on local and global rs-fMRI data in tumor patients and HC population. As a result, the impact of adding nuisance covariates on local and global resting state parameters is different between healthy control (HC) subjects and brain tumor patients. Among the five strategies, Inclusion of PCA of CSF/WM regressors affected local and global parameters differently and it has the largest impact on parameters in healthy control (HC) and tumor patients. There was increase in mALFF values and decrease in fALFF and ReHo values, in addition to introducing connectivity between DMN and SMN in Grade II tumor population that had not been discovered in the other strategies. Also, there is a significant impact of tumor grade on local and global resting state parameters.Ph.D.Includes bibliographical reference
Telomerase-associated apoptotic events by mushroom Ganoderma lucidum on premalignant human urothelial cells
No full textAuthor name used in this publication: Mayur Danny I. Gohel2007-2008 > Academic research: refereed > Publication in refereed journalAccepted ManuscriptPublishedGreen (AAM
The effects of Ganoderma lucidum on initial events related to the Bacillus Calmette-Guérin efficacy and toxicity on high-risk uroepithelial cells : an in vitro preliminary study
No full textAuthor name used in this publication: Yuen, John Wai-Man.2012-2013 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishedC
Synergistic cytotoxic effects of ganoderma lucidum and bacillus calmette guérin on premalignant urothelial HUC-PC cells and its regulation on proinflammatory cytokine secretion
No full textAuthor name used in this publication: John Wai-man YuenAuthor name used in this publication: Mayur-Danny I. Gohel2012-2013 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishedC
Creep of Cracked Fiber Reinforced Concrete
No full textabstract: The concept of Creep is a term used to define the tendency of stressed materials to develop an increasing strain through time under a sustained load, thus having an increase in deflection or having an elongation with time in relation to the short term strain. While the subject of compression creep of concrete is well developed, use of concrete under tension loads has been limited at best due to brittleness of concrete. However with the advent of using fiber reinforced concrete, more and more applications where concrete is expected to carry tensile loads due to incorporation of fibers is gaining popularity. While the creep behavior of concrete in tension is important, the main case of the study is what happened when the concrete that is cracked in service is subjected to sustained loads causing creep. The relationship of opening cracks under these conditions are of utmost importance especially when the serviceability criteria is addressed. Little work has been reported in literature on the long-term behavior of FRC under sustained flexural loadings. The main objective of this study is to investigate the Long Term Flexural Behavior of Pre-Cracked Fiber Reinforced Beams under Sustained Loads. The experimental reports document the effect of loading and temperature on the creep characteristics of concrete. A variety of study has been carried out for the different responses generated by the creep tests based on factors like effect of temperature and humidity, effect of fiber content, effect of fiber type, and effect of different loading levels.
The Creep Testing Experimental Methodology is divided into three main parts which includes: (1) The Pre-cracking Partial Fracture Test; (2) Creep Test; (3) Post Creep Full Fracture Test. The magnitude of load applied to a specific specimen during creep testing was based on the results of average residual strength (ARS) tests, determined using EN14651. Specimens of the synthetic FRC mixture were creep tested at loads nominally equivalent to 30% and 50% of the FR1 value. The creep tests are usually continued until a steady Time versus CMOD response was obtained for the specimen signifying its presence in the secondary stage of creep. The creep recovery response is generated after unloading the specimen from the creep set up and later a full fracture test is carried out to obtain the complete post creep response of the beam under flexure.
The behavior of the Creep Coefficient versus Time response has been studied using various existing models like the ACI 209-R 92 Model and the CEB-FIP Model. Basic and hybrid rheological viscoelastic models have also been used in order to generate the material behavior response. A study has been developed in order to understand the applicability of various viscoelastic models for obtaining the material response of real materials. An analytical model for predicting the Flexural Behavior of FRC under sustained creep loads is presented at the end. This model helps generate the stress strain and Moment Curvature response of FRC beams when subjected to creep loads post initial crackingDissertation/ThesisMasters Thesis Civil Engineering 201
Analysis of genomic differences in SARS-CoV-2 variants, and its Impacts on transmissibility and virulence: Washington and Florida states
No full textThis purpose of this study was to analyze genetic differences between SARS-CoV-2 and its variants, examine how these genetic differences relate to SARS-CoV-2 transmissibility and virulence, and determine the impact of SARS-CoV-2 transmission and virulence for different regions – Washington and Florida – in the United States. Methods: Genetic sequences of SARS-CoV-2 variants were obtained from the National Institutes of Health/National Center for Biotechnology Information and analyzed for genetic variations by the NIH/NCBI Sequence Alignment Tool and the Coronavirus Typing Tool. Data collected by the Center for Disease Control and Prevention, US Department of Health and Human Services, Global Initiative on Sharing All Influenza Data, CoVariants, and Washington State Department of Health was compiled to analyze SARS-CoV-2 health statistics and circulating variants between June 2021 and June 2022. Pearson correlations, unpaired t-tests, and linear regressions were conducted to assess the relationships between health statistics, variants, and region. Results: Alpha, Delta, and Omicron variants had acquired genetic mutations from the original SARS-CoV-2 strain, with Delta obtaining the most. Washington and Florida saw significant relationships between Delta and Omicron and transmissibility; however, no variant had a significant relationship with virulence in either state. similarly, experienced transmission similarly but had significant differences for SARS-CoV-2 virulence. Conclusion: This study shows that Sars CoV-2 Delta and Omicron had significant genetic mutations than Alpha. Omicron being the most significant in both states for transmissibility – cases and hospitalization. The virulence (death) was significantly different between both states.Ph.D.Includes bibliographical reference
