Texas A&M University-Kingsville: AKM Digital Repository
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Effects of electrolyzed reduced water on the Rumen bacterial community of steers consuming a roughage or concentrate diet
No full textElectrolyzed reduced water (ERW) is alkaline water with an oxidation reduction potential less than -800mV produced by an electrolysis process. Human research demonstrates ERW consumption has many beneficial effects, however, intake by ruminants has not been studied extensively. The rumen is a complex environment that can be sensitive to changes in diet which could include water properties. To evaluate ERW effects on the rumen bacterial community of cattle, a two-period, two-treatment crossover design was conducted within each of two experiments. Treatments were control (pH 6.5-7.0; CON) and electrolyzed reduced (pH 8.7-9.5; ERW) water. Experiments differed only in diet: a forage-based diet in Experiment 1 and concentrate-based diet in Experiment 2. Each experiment consisted of two 14-day periods.
Rumen pH and ORP were measured on day 14 at 0, 2, 4, 8, 12, 16, and 20 h after feeding and averaged. Rumen fluid was collected two hours after feeding on days 10 and 12 of each period. Samples were immediately frozen at -80°C until massively parallel sequencing analysis.
Bacterial 16S V4 ribosomal loci were amplified for comparison of rumen bacteria community shifts. QIIME v.2 was used to quality filter and analyze data. Results demonstrate bacterial richness, diversity, composition, and function were significantly different between diets (P ≤0.05) but not affected (P > 0.05) by ERW treatment. Bacterial richness and diversity were significantly higher (P < 0.05) in the forage than the concentrate experiment. According to ANCOM, six bacterial taxa significantly differed between diets at phyla level and 11 bacterial
taxa significantly differed between diets at class level. A total of 3,192 significant functions were identified between experiments with transporters, kinases and oxidoreductases being mostly enriched. Results suggest ERW had no effect on rumen pH, ORP, or bacterial community and confirm diet type alters the rumen bacterial community
Mental models of sustainable water use in South Texas: a multi-stakeholder perspective
No full textFarmers and ranchers must manage their resources to continue to feed a growing population. Agriculture water-use in Texas is a key component to a very dynamic and complex system. The Winter Garden, Costal Bend, and Rio Grande Valley co-exist in South Texas, but the means that they acquire and consume their water resources are widely different. The policies, infrastructure, and water source (i.e., groundwater vs. participation vs. irrigation reliant) in place for each region guide farmers’ management practices and determine agriculture productivity for the region. The mental models instilled in the local farmers and influential stakeholders are a key
component to understanding the structural causes behind current water-use practices and future water sustainability. To better understand the role of heuristics used by farmers and stakeholders when managing water resources, semi-formal interviews were scheduled and conducted with individuals who have a high stake in water resource use and management. Results of the interviews suggest that there is nearly a unanimous consensus among farmers and stakeholders that water supply is limiting and will be increasingly stressed as urban populations continue to grow. Farmers in traditionally agriculture dominant areas have expressed concerns over
urbanization and have stated that it would become even more difficult to continue to farm if water resources are not available. Each region had their own unique problems and concerns. Predominant mental models were synthesized based on dominant themes expressed by the subjects. Concerns for stakeholders in each region included the following: growing bureaucratic oversight and fear over a growing population (Coastal Bend), political subdivision, groundwater levels, and costs of information technology (Wintergarden), and international disputes with Mexico, the lack of environmental inflows, and water quality (Rio Grande Valley). While it would be unreasonable to create blanket state-wide policies concerning water supply and quality, utilizing regenerative soil health techniques tailored to the local level may be an unexplored leverage point for stakeholders to improve on-farm water-use efficiency through improvements
to soil functions. Several feedback archetypes were identified in multiple responses, including Tragedy of the Commons and Success the Successful. Public outreach and water resource education is also vital, given that most people are unaware of these feedback processes that will
continue to threaten agricultural productivity in south Texas through reduced water supplies
Comparison of wireless data collection and remote monitoring techniques
No full textThe advancement of technologies, such as Wireless Sensor Networks (WSN) and Unmanned Aircraft Systems (UAS), has furthered opportunities for effective remote monitoring. Specifically, soil moisture monitoring is a crucial area of interest due to its impact on irrigation management decisions and is essential to crop health. This investigation compares two major kinds of WSN data retrieval: Static data collection and Mobile data collection. The former was achieved with a commercially available solution, while the latter used drone technology and a custom approach. The custom solution was developed as a lower-cost alternative using 3D-printed parts for the sensor and drone communication modules. After evaluating the advantages of both methods, their overall viability is compared according to various categories. Key differences include availability, data collection, overall cost, ease of operation, data regularity, and scalability. The static and mobile methods were implemented in the field, and conclusions were drawn. The commercial static solution offers easy operation and faster data retrieval, while the custom mobile solution offers advantages such as a lower cost and independent operation. Additional changes are discussed regarding improvements to the custom solution, such as adding GPS markers on the custom sensor nodes and implementing a fixed-wing drone with path planning
On the irregular hexagon tessellation for connected k-coverage in planar wireless sensor networks
No full textIn wireless sensor networks (WSNs), the quality of service in terms of network connectivity and sensor coverage is critical. The two most significant functions of a sensor in planar (or two-dimensional) WSNs are sensing and communication, and these functionalities are typically assessed using the two metrics, namely coverage and connectivity. We examine the issue of planar k-coverage, where every point in a planar field of interest (PFoI) is covered by at least k sensors at the same time with k ≥ 1 being a natural number. To be more specific, the sensor placement issue was addressed, and the sensor density needed to k-cover a PFoI was computed. In this thesis, we focus on the connected k-coverage problem (CCkP) in planar WSNs (PWSNs) with the goal to achieve k-coverage of a PFoI and connectivity among all the sensors participating in the k-coverage process. First, a FoI should be tiled using planar convex polygonal tiles, which do not yield any gap or overlap. Second, we use these planar tiles to calculate the required sensor density for planar k-coverage. Third, we identify the relationship that must exist between the sensors’ communication and sensing ranges to ensure network connectivity. Fourth, we propose energy-efficient k-coverage approaches using the “best” planar convex polygonal tile. Fifth, we use the results of the simulation to support our mathematical analysis. Our goal is to extend the network lifespan, while achieving k-coverage of a PFoI with the smallest number of sensors
Early College High School: qualitative perceptions of administrators and teachers in Region 2 of South Texas on closing the achievement gap for Latino students
No full textThis study explored the perceptions of administrators and teachers serving in their first 4 years of Early College High Schools (ECHS) in Region 2 of South Texas regarding their views on how these educational institutions are closing the achievement gap between Latino and non-Latino students in low socioeconomic school districts. Interview protocol questions tapped subjects’ perceptions regarding student achievement, discipline, and engagement, as well as whether they believed the program’s design effectively increases enrollment and achievement of Latino students on college campuses, where they have been traditionally underrepresented and underserved. A qualitative research methodology was employed—specifically, naturalistic inquiry. Purposeful sampling technique was used to select participants who met the criteria for this study: seven administrators and seven teachers from Region 2 of South Texas in ECHS facilities of predominantly Latino students. Capturing their experiences by means of interviews contributes significantly to the research. Data were collected during face-to-face Zoom video conferencing interviews using open-ended questioning, active engagement, and observation. All data were analyzed for developing themes and coded using the continuous proportional technique. Following analysis that included two cycles of coding, and produced 31 codes, six themes emerged: student traits, curriculum/rigorous instruction, school design, Latino family culture, financial sustainability plan, and bridge educational gaps. Key findings indicate that the interviewees uniformly agreed the Early College High School philosophy and processes do support student achievement, discipline, and engagement, plus that the ECHS program designs facilitate increases in enrollment and achievement of Latino students on college campuses. Ultimately, this works toward closing the achievement gap between Latino and non-Latino students in low socioeconomic school districts and beyond. Subjects in this study expressed particular concern that students lack access to technology and internet, since many Latino families do not have home internet or computer access. To help mitigate this situation, school systems seeking to implement ECHS programs might seek to obtain additional funding through grants and other resources to enable students to rent or borrow books and computers, and perhaps support or at least subsidize family internet subscriptions. This study will inform and benefit school districts considering whether to seek or desiring to attain a designation of Early College High School
Texas medical students attitudes towards Spanish and Acceptance of Spanish instruction in medical school
No full textThe fast-growing Hispanic/Latino population has increased the number of Spanish speakers seeking education and healthcare in the United States since 1990 (Guzman & McConnell, 2002; Hellerstedt, 2018; U.S. Bureau of the Census, 1993). Assisting Spanish-speaking patients challenges the health system nationwide, mainly in states with large Hispanic/Latino populations, such as Texas. Despite the need to increase the bilingual workforce in health care, there is a lack of information about the methodology and outcomes of Spanish courses in U.S. medical schools. The aim of this correlational, cross-sectional study, grounded in the Theory of Planned Behavior [(TPB) Ajzen, 1985, 1991] was to contribute to filling the knowledge gap in medical Spanish research by determining the relationship between Texas medical students' attitudes toward Spanish, and the extent to which they are amenable to receiving Spanish courses in U.S. medical schools. The sample included 141 medical students from seven Texas universities. The study employed an online survey for data collection.
Data analysis was performed employing Microsoft Excel and the R statistical software. Descriptive statistics, inferential statistics, and cross-tabulations were performed to analyze data. Findings showed that Texas medical students hold positive attitudes toward the Spanish language to a great extent (93.62% / n=132). In addition, data demonstrated that Texas medical students are amenable to receiving Spanish instruction in medical school (87.94% / n=124). Spearman's correlation was 0.44 (p<0.05), which enabled the researcher to observe a positive and moderate monotonic correlation between medical students' attitudes toward Spanish and their amenability to receiving Spanish instruction in medical school. Based on the results, it is recommended for medical schools to advertise medical Spanish offerings to create awareness among students about the existing programs. Future research could expand this study beyond Texas to compare results. Researchers can replicate this study by employing a qualitative method to explore medical students' perceptions and experiences about medical Spanish instruction in more detail
Anatomical and morphological predictors of transpiration rate in Epipremnum aureum
No full textUnlike other living organisms, plants survive and thrive in places throughout their lives. They live and survive on passive absorption of nutrients and transpire water in the process. The water so transpired evaporates into the atmosphere in the soil-water-root-plant-atmosphere evapotranspiration continuum. It indeed means that effective evapotranspiration indicates effective nutrient absorption since it is a passive process. However, some important crop growth questions have not been sufficiently addressed including:
I. What combination of plant anatomical and morphological growth parameters predict plant transpiration?
II. Which feature, anatomical or morphological, is dominant in prediction?
III. What is the level of accuracy for such a prediction?
IV. Is predictability improved with statistical manipulation of anatomical characteristics over morphological parameters or vice versa?
In this proposed thesis research, leaf area, stomatal conductance, crop run length, rate of transpiration, fresh leaf biomass, dry root biomass, fresh root biomass, dry leaf biomass, leaf temperature, cell wall thickness, and cell lumen diameter will be studied as morphological and anatomical growth and development parameters using Epipremnum aureum. The data will be statistically analyzed using SAS 9.01 to decipher the species' transpiration rate's anatomical or morphological growth and development predictors. Also, the degree of predictability of such parameters and the suitable prediction equation will be generated
Response of cotton varieties to potassium fertilizer application in South Texas
No full textCotton (Gossypium hirsutum L.) is a leading cash crop in Texas which accounts for 40% of total cotton produced in United States. Potassium is one of the most important macronutrients which plays a significant role in cotton plant growth and development. Studies indicated that there are potassium deficiencies observed in cotton in south and central Texas. The objective of this study is to determine and compare the effect of potassium fertilizer application rates and application methods on cotton plant height, canopy, yield and quality of the cotton. Three varieties of cotton were compared, NG 5711 B3XF, PHY 480 W3FE, and FM 1953GLTP and four different rates of potassium fertilizers, 0 Kg ha-1, 33.6 Kg ha-1, 50.4 Kg ha-1, and 67.2 Kg ha- 1 applied with two different application methods, before the planting and as foliar spray. Results indicate that potassium application at 50.4 kg ha-1 had a significant effect on staple length, uniformity, and yield in 2020, however this significance was not seen in 2021. The varieties had a significant effect on yield and some of the quality parameters such color grade, staple length, strength and uniformity but the application methods didn’t have any significant effect on plant height, canopy, yield, and quality. Overall, the results of this study are inconclusive, and more research is required considering various dynamic cotton development parameters such as plant density, boll count, potassium content in leaves, leaf area index, plant growth stages, and boll growth stages and also evaluating the effects of potassium fertilizer applications on cotton in different soil potassium levels, different application rates and various climatic zones
Study on artificial intelligence-based ransomware detection for digital substations
No full textRansomware is a modern form of malware that prevents victims from accessing their computer systems, important document files/folders, etc. The attacker would not release them until a ransom was paid through some secret channels. Ransomware has become a serious threat to the current computing world, requiring immediate attention to prevent it. Ransomware attacks can also have disruptive impacts on operation of smart grids including digital substations. This thesis research proposes a ransomware attack modeling method targeting disruptive operation of a digital substation and investigates an artificial intelligence (AI)-based ransomware detection approach. The proposed ransomware file detection model is designed by a convolutional neural network (CNN) using 2-D grayscale image files converted from binary files. The experimental results show that the proposed method achieves 96.22% ransomware detection accuracy, which is better than the other methods reported in the literature, including the RF method based on Ngram of opcodes, with an accuracy of 91.43%, which was best among its peers
Leptin and fibroblast growth factor 2 influence gene expression and cellular morphology during angiogenic progression
No full textDuring wound healing the re-establishment of vasculature is a vital process as it provides the substrates required for tissue repair. Therapeutic practices have been established to accelerate the rate of injury repair, such as the application of homogenized adipose tissue, which has potent angiogenic factors including leptin and fibroblast growth factor 2 (FGF2). Receptors for leptin and FGF2 have been identified on mature adipocytes (MA) and vascular endothelial cells (VEC), which suggests that they are involved in vasculature processes of adipose tissue. Therefore, it is hypothesized that leptin and FGF2 influence angiogenic progression in adipose tissue by regulating gene expression and influencing morphological changes of VEC. The objectives were 1) to determine the effect of FGF2 on leptin expression and leptin on FGF2 expression in MA and stromal vascular fraction cells (SVF, VEC, pre-adipocytes, fibroblasts, pericytes, etc.) and 2) to determine the effects of MA, FGF2, and leptin on VEC morphology during angiogenic progression. Adipose tissue from 15 pre-pubertal crossbred gilts (60 ± 20 d) was collected, enzymatically dispersed, processed for cell culture, and allocated to either a MA and SVF angiogenic factor regulation experiment or a morphology experiment. For the angiogenic factor regulation experiment, a set of MA and SVF cells from five gilts were incubated with porcine FGF2 (0M, 10-11M, 10 -10M, 10-9M) or porcine leptin (0M, 10-12M, 10-11M, 10 -10M, 10-9M). For the VEC morphology experiment, MA or SVF from ten gilts were incubated separately for 24 h. The SVF cells were cultured in attachment media and MA were incubated in standard culture media for 24 h at which time MA were added to SVF cells. Cultures were allocated to either FGF2 and FGF2Ab (n=5) or leptin and leptinAb (n=5) treatment and cultured for an additional 24 h. In the MA and SVF angiogenic factor regulation experiment, FGF2 increased leptin expression (P<0.05) and leptin decreased FGF2 expression (P=0.03) in MA. In the VEC morphology experiment, FGF2 upregulated leptin and FGF receptor (FGFR2c) expression (P<0.05). However, leptin tended to increase (P=0.1) FGF2 expression. In the absence of MA, there was limited VEC morphological progression, but with addition of MA, and an additional 24 h, morphology of VEC significantly increased (P< 0.001). Treatment with FGF2 did not appear to affect elongation, sprouting, or nascent tube formation of VEC, but tended to decrease (P=0.1) the number of vessel tubes formed. Exogenous leptin did not appear to influence VEC morphology. However, reducing available endogenous leptin with leptinAb treatment resulted in fewer elongated VEC (P<0.05) and nascent tubes (P<0.01) and tended to decrease (P=0.07) vessel tube formation. Collectively, these studies determined the regulatory effects of FGF2 and leptin on gene regulation and VEC morphology in MA and SVF cultures. Regulation of leptin and FGF2 expression in MA and the influence of MA on VEC morphology implies that MA are critical for advancing adipose tissue revascularization