The LAIR at East Texas A&M
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The Static and Dynamic Behavior of Steel Storage Tanks over Different Types of Clay Soil
No full textSteel storage tanks are widely used in different fields. Most of these tanks contain hazardous materials, which may lead to disasters and environmental damage for any design errors. There are many reasons which cause the failure of these tanks such as excessive base plate settlement, shear failure of soil, liquid sloshing, and buckling of the tank shell. In this study, five models of above-ground steel storage tanks resting over different types of clay soils (medium-stiff clay, stiff clay, and very stiff clay soils) are analyzed using the finite element program ADINA under the effect of static and dynamic loading. The soil underneath the tank is truly simulated using a 3D solid (porous media) element and the used material model is the Cam-clay soil model. The fluid in the tank is modeled depending on the Navier–Stokes fluid equation. Moreover, the earthquake record used in this analysis is the horizontal component of the Loma Prieta Earthquake. The analyzed tanks are circular steel tanks with the same height (10 m) and different diameters (ranging from 15 m to 40 m). The soil under the tanks has a noticeable effect on the dynamic behavior of the studied tanks. The tanks resting over the medium-stiff clay (the weakest soil) give a lower permanent settlement after the earthquake because of its low elastic modulus which leads to the absorption of the earthquake waves in comparison to the other types of soil. There are 29.6% and 35.6% increases in the peak dynamic stresses under the tanks in the cases of stiff clay and very stiff clay soils, respectively. The maximum values of the dynamic vertical stresses occur at a time around 13.02 s, which is close to the peak ground acceleration of the earthquake
Comprehensive List Satirical News Websites
No full textIndex of Satirical News Websites created by Dr. Salvatore Attardo
Performance of Rubberized Concrete and the Effect of Temperature and Stainless Steel Fibers
No full textRubberized concrete is widely used in construction by utilizing the advantages of partially replacing fine or coarse aggregate with rubber to enhance several properties of concrete and provide an environmentally friendly solution. This paper experimentally explores the influence of utilizing crumb rubber (CR) as an alternate coarse aggregate in concrete. Concrete specimens were prepared with different percentages of rubber (0%, 5%, 10%, 15%, and 20%). Additionally, other parameters, such as freezing–thawing cycles, temperature, and stainless steel fibers (SSFs), were investigated. The workability of fresh concrete and the compression properties of hardened concrete were examined. Reductions in the mechanical properties of rubberized concrete were obtained. The compressive strength reductions ranged between 13% and 50%, based on the percentage of CR in the concrete mix. However, a lesser unit weight and higher toughness were obtained relative to conventional concrete. The average unit weight decreased by 1.3%, 2.5%, 3.4%, and 5.7% of the control mixture when 5%, 10%, 15%, and 20% of the CR were incorporated into the concrete mixtures, respectively. Regression models to predict the compressive strength and unit weight of concrete with CR were developed. In addition, a life cycle cost analysis (LCCA) to identify and quantify the possible benefits of using CR in concrete mixes was carried out. Using rubberized concrete mixtures for thin white topping offered a slightly lower net present value compared to the ordinary concrete mix
Pyrimidine Biosynthesis and Ribonucleoside Metabolism in Species of \u3ci\u3ePseudomonas\u3c/i\u3e
No full textPyrimidine biosynthesis and ribonucleoside metabolism in species of Pseudomonas was the focus of this review, in relation to their current taxonomic assignments in different homology groups. It was of interest to learn whether pyrimidine biosynthesis in taxonomically related species of Pseudomonas was regulated in a similar fashion by pyrimidine base supplementation or by pyrimidine limitation of pyrimidine auxotrophic strains. It was concluded that the regulation of pyrimidine biosynthesis in Pseudomonas species could not be correlated with their taxonomic assignment into a specific homology group. Pyrimidine ribonucleoside metabolism in Pseudomonas species primarily involved the pyrimidine ribonucleoside salvage enzymes nucleoside hydrolase and cytosine deaminase, independently of the Pseudomonas homology group to which the species was assigned. Similarly, pyrimidine base catabolism was shown to be active in different taxonomic homology groups of Pseudomonas. Although the number of studies exploring the catabolism of the pyrimidine bases uracil and thymine was limited in scope, it did appear that the presence of the pyrimidine base reductive pathway of pyrimidine catabolism was a commonality observed for the species of Pseudomonas investigated. There also appeared to be a connection between pyrimidine ribonucleoside degradation and the catabolism of pyrimidine bases in providing a cellular source of carbon or nitrogen independently of which homology group the species of Pseudomonas were assigned to
Exploring the Relationship Between Earned College Readiness Indicators and First-to-Second-Year College Persistence in Under-Resourced Students
No full textThis study will examine the first-to-second-year college persistence of students who graduated from Fort Worth Independent School District (FWISD) in the class of 2018. The study seeks to understand how the attainment of college readiness indicators correlates with college persistence in two categories of students, resourced and under-resourced. The state of Texas has set college readiness indicators as a part of College, Career & Military Readiness (CCMR) standards. Although there is a focus on increasing the number of students meeting CCMR across the state, whether these indicators are helpful in predicting college persistence remains a topic of discussion. As a district with a large percentage of under-resourced students, the promoted standards should prepare students for success in entry-level college courses without remediation.This study analyzes the relationship between each college readiness indicator and its correlation with first-to-second-year persistence by student category
Negotiating with Terrorists: Trauma, Terrorism, and Power in 9/11 Adolescent Novels
No full textHistory has proven that tragedies can be incomprehensible at the time they occur; it is through this incomprehensibility that they have the power to leave their mark on the literary world. However, it was not until the rise of trauma theory throughout the 1990s that scholars were presented with a new way to analyze novels that depict or reference traumatic events. Trauma theory opens the door for new research, particularly in adolescent fiction about the terrorist attacks of September 11, 2001. Due to the highly publicized event, adolescents could easily witness the horrors of the attack, but the rise of the sub-genre of adolescent 9/11 fiction after 2003 gave young readers a way to comprehend the incomprehensible. However, relatively little research about the emerging sub-genre exists. Terrorism is a force that subjects people to ongoing fear. It does not allow the characters found in 9-ll literature to negotiate power directly, which is how they are commonly known to successfully navigate through the “coming of age” process. The protagonists in the ten novels I have chosen for this project must find a way to gain a level of power outside the traditional means. They accomplish this through helping others, which in turn allows them to accept that their reality now includes terrorism. This research will explore how protagonists must obtain power indirectly by helping others, which allows them to gain a level of power and accept that their reality now includes terrorism. It will utilize trauma theory and supplement with research on growth and power in adolescent fiction
A Narrative Inquiry Into the Lived Experiences of Resilience in African American Secondary Male Teachers on Predominantly White Campuses
No full textThis narrative inquiry uses the framework of Connelly and Clandinin to restory the experiences of three African American secondary teachers in suburban or rural campuses. African American teachers are underrepresented in the field of education and educational research. Their stories of personal resilience during a time of extreme challenge due to racial and political tensions in the country and the worldwide COVID-19 pandemic can give insight into the sources of resilience that can best be used by school leaders to help support and retain this group of teachers and others in the classroom. This study explores the personal narratives of three African American male teachers through semistructured interviews and examines the teachers’ stories using a framework that connects Polidore’s theory of resilience, relational- cultural resilience theory, and Fraser’s social justice theory to guide the narratives and data analysis process. Through the restorying process, the study looks to identify the dominant traits of resilience that help to retain African American teachers in the classroom and gain anunderstanding of this underrepresented group\u27s experience in the classroom and the ways it may differ from the dominant teacher demographic group
School Turnaround: Student Achievement Sustainability
No full textThe lack of access to high-quality schools creates an achievement gap that limits students’ access to future earnings and longevity, exacerbating equity concerns across the nation where struggling, low-performing schools are disproportionately responsible for educating students living in poverty. Large Urban School District’s Accelerating Campus Excellence (ACE) program for school turnaround represented a model with longitudinal data for ascertaining its lasting educational impact on students. The purpose of this study was to determine if the implementation of the ACE model yields a statistically significant difference in scores between ACE students and non-ACE students. This study was conducted via a quantitative approach and a quasi-experimental design to examine if there was a difference in student growth in reading and mathematics due to the type of campus program of ACE versus non-ACE. The data for this study came from the Texas Education Agency’s STAAR Grades 3 through 8 reading and mathematics assessments. The data were the ACE and non-ACE students’ 2015-2016 elementary STAAR reading and mathematics test scores and the same students’ 2018-2019 STAAR reading and mathematics scores and represented a 4-year span. Once the students were matched between the two equally sized groups of ACE and non-ACE schools, independent t tests were used to ascertain if there were differences between the groups on student growth between the STAAR reading and mathematics tests for Grades 3 and 6. For this research, the independent variable was the type of campus program support received (ACE and non-ACE), and the dependent variable was 2018-2019 student growth as measured by percentile scores on the Grades 3 and 6 STAAR reading and mathematics tests. Findings revealed there was no statistically significant difference between ACE and non-ACE students on STAAR reading percentile scores; the null hypothesis failed to be rejected. Also, there was no statistically significant difference between ACE and non-ACE students on STAAR mathematics percentile scores; the null hypothesis failed to be rejected. Though both null hypotheses were retained, the students from ACE schools performed higher on the STAAR reading than non-ACE students. Of note, the overall small effect size could represent a practically significant STARR improvement, particularly if the improvement applied uniformly to all students and was cumulative over time
Modeling the Thermal Evolution of MXB 1659-29
No full textLow-mass x-ray binaries consist of one neutron star or black hole and a companion star of lower mass than that of our sun that is cannibalized over time, resulting in a brilliant x-ray burst from the former. The observation of the neutron star\u27s cooling curve when it is quiescent can give us insight to the internal structure of the crust as it comes into equilibrium with the core. Using UNAM Dany Page\u27s 1D fortran cooling code, NSCool, we have modelled multiple generated equations of state against data gathered with Chandra and XMM-Newton from the double episode accretion source, MXB 1659-29, to gain constraints on the neutron star\u27s crust. Varying chosen parameters allows us to see their direct effects on the predicted thermal evolution of these equations of state and can aid in the adjustment of them to give the most accurate fit
Generation of DNA Codes from Abelian Groups
No full textIn this work, we present a circulant-matrix construction for reversible codes derived from Abelian groups. By employing this matrix construction, we show how one can construct reversible codes of over the finite field F4. We apply this in the construction of synthetic DNA codes that satisfy the Hamming distance, the reverse, the reverse-complement, the GC-content constraints, free from secondary structures and are complete conflict free. With the generated DNA codes satisfying all these constraints, we get codes that are more chemically active and highly useful for DNA computing, storage, etc