Texas A&M University-Kingsville: AKM Digital Repository
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Relationship between mindset and self-efficacy among special education teachers in Texas region 2
No full textThis dissertation investigated the relationship between mindset and self-efficacy among special education teachers in Region 2 of Texas. While approximately 500,000 students are provided special education services in Texas public schools, special education students perform significantly lower on state assessments in reading and math than their non-disabled peers. Between 70-85% of special education students in the 3rd and 8th grades in Texas perform below their non-disabled peers on state assessments. Special education teachers must persevere to meet the demands of the special education population. The literature review revealed a positive correlation between teachers’ mindset, self-efficacy, and student achievement. The purpose of this study was to examine the extent of the relationship between growth mindset and overall self-efficacy, self-efficacy in student engagement, self-efficacy in instructional strategies, and self-efficacy in classroom management among special education teachers in Texas Region 2. The concept of mindset framed this study. Mindset is a coalescence of two theories, social cognition theory and self-efficacy theory. An analysis of the relationship between special education teacher mindset and self-efficacy was conducted. The bivariate Spearman Rho was used to analyze data. The results of this study revealed that there is no statistically significant correlation between mindset and overall self-efficacy, self-efficacy in student engagement, self-efficacy in instructional strategies, and self-efficacy in classroom management among special education teachers in Texas Region 2. However, this study also indicates that positive interventions, mindset changes, and teacher self-efficacy correlate with improvements in student learning because the statistical analysis results show these variables all move in the same direction. These results can assist districts, principals, regional education service centers, and other staff responsible for ensuring successful learning outcomes for special education students.
Keywords: special education teachers, mindset, self-efficacy, south Texas, student achievemen
Brain tumor segmentation from brain MRI data using deep neural networks
No full textBrain tumor segmentation is an important task to be performed in analyzing the brain Magnetic Resonance Images (MRI). These brain MRI segmentation techniques help in making a biomedical image processing application for supporting neurologists and brain disease patients. There is need for automatic brain tumor segmentation methods to facilitate neurologists for diagnosis. This work implements a convolutional neural network based variational autoencoder model, modified with an additional flattening layer, on four different scenarios. In the first scenario, the model was trained on the BraTS-2019 dataset with a batch size of 1 over 10 epochs, and then tested on the BraTS-2018 dataset. In the second scenario, the model was trained on the BraTS-2018 dataset with a batch size of 1 over 10 epochs, and then tested on the BraTS-2019 dataset. In the third scenario, the model was trained on the BraTS-2019 dataset with a batch size of 2 over 20 epochs, and then tested on the BraTS-2018 dataset. In the fourth scenario, the model was trained on the BraTS-2018 dataset with a batch size of 2 over 20 epochs, and then tested on the BraTS-2019 dataset. The average Dice coefficient values of the whole tumor segmentation were 0.89003, 0.88551, 0.88569, and 0.9089, for the four scenarios, respectively. This proposed method’s accuracy on average was 0.893, which was a higher accuracy for whole tumor segmentation than other brain tumor segmentation methods compared in this work
Modeling hydrogenation of maleic acid to tetrahydrofuran in a trickle bed reactor
No full textWorldwide demand for specialty chemicals for advanced materials, such as tetrahydrofuran, (THF) continue to increase steadily. Uses of these chemicals range from intermediates in production of spandex fibers and elastomers, constituents in pharmaceuticals, high grade plastics, adhesives, and solvents. This study provides insight into the performance of a three-phase continuous co-current up-flow fixed-bed reactor using a pseudo-homogeneous model for the hydrogenation of maleic acid (MAC) to THF. A bimetallic Re/Rh-on-carbon spherical shaped catalyst with diameters of 0.5 mm, 1 mm, and 10 mm were selected as the preferred catalysts. The reactor temperature was assumed to be isothermal as might typically occur in a catalyst screening experiment. The intrinsic reaction kinetics for the series hydrogenation are described by a Langmuir-Hinshelwood model whose parameters were determined by regression analysis of stirred slurry batch reactor data. The combined effects of feed composition of MAC and succinic acid (SAC), liquid-phase superficial velocity, hydrogen pressure, particle diameter, reactor geometry, and catalyst loading on reactor performance were studied. Pressure effects indicated that while system pressure is important, it is not the parameter that is the main driver for optimized yields of THF. Contact time of 500 seconds is optimal compared to 5000 seconds or 50 seconds for this continuous flow system being modeled with the reactor volume of 500 cubic centimeters. Catalyst loading density resulted in slightly higher THF yields, an indication that the catalyst maybe highly active. The surface reaction flow profiles in the bed are key to performance of the reactor to achieve desired THF flow rate and subsequently yields. Liquid feed composition suggests that either splitting the reaction network between two different reactors or just starting off with succinic acid or even gamma butyrolactone may be a more optimized option compared to a single bimetallic catalyst bed. Pressure effects did impact selectivity, resulting in better selectivity to tetrahydrofuran at the lower pressure and lower catalyst loading density. Effects of hydrodynamics lead to a conclusion that hydrodynamics plays a majority role in the operation of a three phase continuous flow reactor, which will consequently impact reactor yields of the desired produc
Virtual browser
No full textMobile devices are an important aspect of everyone’s life and the security of these devices is essential. Major attacks come from browsers or applications exposed to the internet. To protect against such attacks, a strong defense is necessary. Attacks like xHelper and WannaCry have triggered global outrage in the past and it may be triggered again at any time. Various techniques like antivirus scanning, secure coding, restricting code execution, code analysis have failed to provide security. In this research, the virtual browser, a system that isolates a browser to the remote cloud and accesses it through Remote Desktop Protocol (RDP), is proposed. The virtual browser accomplishes this by isolating the client browser to the remote cloud and downloading the necessary content from the remote browser through antivirus scanning. This action will create a strong defense from the internet vulnerabilities.
Despite a number of developments in remote desktop technology, it needs to be extended further at the application level. It can be used in the field of application protection and security. In this research work, the security aspect of the browser is explored. Various browser vulnerabilities coming from the JavaScript extension plugin have been analyzed to determine its strengths and weaknesses. Also, protocols like VNC (Virtual Network Computing) and RDP have been researched and analyzed. Based on this research, a new architecture for dealing with browser security is proposed.
A remote browser, with all the computing resources and a custom-built browser extension with end-to-end synchronization capability, is created. An RDP gateway service is set up to channelize the client and the remote browser traffic. A client browser will set up a session through an RDP gateway service with the remote browser and display the remote browser’s contents. A proof of the concept simulating the proposed environment has been implemented and is discussed to examine strengths and
Interaction of Bradyrhizobium and Trichoderma on the growth, development and yield of Arachis hypogaea L. (Peanuts)
No full textPeanut (Arachis hypogaea L.), is an important legume crop in the world. Continuous cultivation of the species in the same land contributes to the accumulation of root exudates leading to increased soil pathogens and decreased yield. Endophytic fungi have been known to possess the ability to metabolize soil phenolic acids. Trichoderma harzianum is a naturally occurring plant growth-promoting (PGP) endophytic fungi that can enhance plant growth, nutrient uptake, and tolerance to biotic and abiotic stresses. Separately, Bradyrhizobium spp. a biological nitrogen-fixing (BNF) bacteria interacts with peanut roots in nodule formation, thereby promoting nitrogen fixation. The dynamics of the symbiotic association between these two organisms were evaluated in the lab and greenhouse conditions. Peanuts were cultivated in pots inoculated with Bradyrhizobium and Trichoderma in four replicated treatments to evaluate growth, development, and yield. The in vitro study results indicate that seeds treated with Bradyrhizobium and Trichoderma separately had better growth (p=0.0118) compared to the co-inoculation and control. Whereas, results of greenhouse studies showed that seeds inoculated with both microbes, and those inoculated with Bradyrhizobium alone had higher dry biomass (p<0.0001) as well as higher chlorophyll content (p<0.0001) compared to the other treatments. The results showed that seeds treated with Trichoderma alone had better germination and initial growth and seeds treated with Bradyrhizobium increased the overall plant height, chlorophyll, and biomass. Understanding the iv interaction of fungal endophytes and rhizobial bacteria will help in both nutrient and disease management of Arachis hypogaea L
Vegetation and wildlife response to a native-grassland restoration
No full textNon-native invasive species of both flora and fauna are profusely degrading community biodiversity. One such species that has a significant ecological impact is buffelgrass (Pennisetum ciliare). Buffelgrass was introduced from Africa to Texas in the early 1900’s for cattle forage. Since then, millions of hectares have been planted with or invaded by buffelgrass, creating near monocultures. These monocultures of non-native vegetation have been shown to reduce diversity of the herbaceous plant, bird, butterfly, and small mammal communities. Restorations may be able to mitigate challenges that non-native grasses create in ecosystems. My research involved documenting plant (grasses and forbs) and wildlife response (grassland breeding birds, grassland wintering birds, butterflies, and small mammals) to a grassland restoration (118 ha) in La Salle County, Texas during 2013–2019. A general trend from the 4 taxa (native plants, birds, butterflies, and small mammals) was the numerical increase in species richness, species evenness, and species diversity on the restoration site compared to a control. This information is critically needed to evaluate the effectiveness of large-scale restoration in areas invaded by non-native species such as buffelgrass on native plants and important wildlife communities. My results suggest native grassland restoration is possible in a landscape dominated by buffelgrass on cultivatable soils and can benefit several important taxa positively
The Inter-American Conference for the Maintenance of Peace
No full textPan – America relations took on a new interest to the writer after she had made a study of Latin American attitude towards the Monroe Doctrine. From this interest came the desire for further study in the same field. The accompanying thesis is the result. Much of the material was taken from The New York Times, most of it had, of necessity, to be collected from current periodicals
An early history of Cameron County
No full textCameron county is situated in that southernmost area of Texas known as the lower Rio Grande Valley. The Rio Grande River, as the international line of demarcation between the United States and Mexico, is the southern boundary of the county. On the east it is bounded by the Gulf of Mexico, on the north by Willacy County, and on the west by Hidalgo County
Eastern and western traditions as reflected in the writings of William Vaughn Moody
No full textAmong the American poets of the turn of the past century, William Vaugh Moody presents one of the most difficult problems to interpreters. The extraordinary eclecticism of his mind and art can be understood only after an investigation of the vital forces at work upon his personality. among these forces, the two which came into the greatest conflict were the older, conservative, belletristic traditions of his early years at Harvard and the violent individualistic impulses of his pedagogical years at Chicago
The Maderist and Constitutionalist revolutions in Mexico (1910-1915)
No full textA very fervent desire of the writer to contribute with an insignificant atom to the better understanding of our country and our neighborhood to the South has caused her to translate, check historical facts, and present as a thesis the first ten chapters of the book entitled Resona Historica Mexicana de 1910 en Adelante. So that mutual friendly relations develop, it is agential that both candidates for friendship know each other's history. To know a friend's life one must hear about it from own lips as to know how he feels about every incident in his life. The story told by outsiders would not help as much as when it is told by the one affected or by one of the ones affected