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Blended Learning Implementation Among Mathematics Students: A Comparison to Traditional Learning Platform
No full textTechnology enables innovation in teaching and learning. Extant educational research has been focused on comparison between learning platforms, namely traditional and blended learning environments. The purpose of this study examined the differences between students’ performance in a Blended and traditional college course and it compared the performance of diverse students’ population enrolled in the Precalculus courses in an urban campus setting. The research questions of this study are (a) is there a difference in the student performance as measured by final course grade in Precalculus between students attended the blended or the traditional course?, (b) is there any difference in the performance as measured by final course grade in Precalculus between Male and Female students in either blended or traditional course?, (c) is there any difference in the student performance in either blended or traditional course as measured by final course grade in Precalculus based on race. This study deployed quantitative research design using a convenience sampling technique. A significant difference occurred in the student performance in Precalculus between blended and traditional learning courses. Also, a significant difference occurred in the performance in Precalculus between Male and Female students in either blended or traditional course. According to race, blended learning had positive effect on student performance. This study contributes as an addition to previous research as the focus on Precalculus course at Texas A&M that has never been studied, which may encourage faculties to build an effective blended learning strategy to improve student performance among its diverse student population
Regulation of corA, the Magnesium, Nickel, Cobalt Transporter, and Its Role in the Virulence of the Soft Rot Pathogen, Pectobacterium versatile Strain Ecc71
Get PDFPectobacterium versatile (formally P. carotovorum) causes disease on diverse plant species by synthesizing and secreting copious amount of plant-cell-wall-degrading exoenzymes including pectate lyases, polygalacturonases, cellulases, and proteases. Exoenzyme production and virulence are controlled by many factors of bacterial, host, and environmental origin. The ion channel forming the magnesium, nickel, and cobalt transporter CorA is required for exoenzyme production and full virulence in strain Ecc71. We investigated CorA’s role as a virulence factor and its expression in P. versatile. Inhibiting the transport function of CorA by growing a CorA+ strain in the presence of specific CorA inhibitor, cobalt (III) hexaammine (Co (III)Hex), has no effect on exoenzyme production. Transcription of pel-1, encoding a pectate lyase isozyme, is decreased in the absence of CorA, suggesting that CorA influences exoenzyme production at the transcriptional level, although apparently not through its transport function. CorA− and CorA+ strains grown in the presence of Co (III)Hex transcriptionally express corA at higher levels than CorA+ strains in the absence of an inhibitor, suggesting the transport role of corA contributes to autorepression. The expression of corA is about four-fold lower in HrpL− strains lacking the hrp-specific extracytoplasmic sigma factor. The corA promoter region contains a sequence with a high similarity to the consensus Hrp box, suggesting that corA is part of Hrp regulon. Our data suggest a complex role, possibly requiring the physical presence of the CorA protein in the virulence of the Pectobacterium versatile strain Ecc71
Dominant ecological processes and plant functional strategies change during the succession of a subtropical forest
Get PDFUnderstanding community assembly process could enhance forest conservation and restoration, while which dominant ecological process drives the community assembly during forest succession is still controversial. In this study, the phylogeny-based and functional trait-based indicators were used to investigate the community assembly processes during forest succession in southern China. 30 dominant species and 33 functional trait indicators related to plant competition, reproduction, and defense strategies, 7 environmental factors related to light availability and soil nutrients, and species richness were selected to explore the dominant ecological processes during succession via Monte Carlo method, structural equation model, multiple linear regression, and one-way ANOVA analysis. Results showed that both the community phylogenetic and functional trait structures changed during succession. Phylogenetic structure clustering and functional trait clustering were evident in early succession. In middle succession, the phylogenetic structure and functional trait structure were randomly dispersed. In middle and later succession, the phylogenetic structure clustering, functional trait clustering, and functional trait evenly dispersed were found. The environmental factors, especially the soil P content, and species richness were found to have significant effects on the community assembly processes during succession. Dominant species in early succession always occupied acquisitive strategies and had high light-use ability and low investment in defense, but dominant species in later succession showed more conservative strategies and exhibited diverse defense strategy, reproductive strategy, and light and nutrient resource-use strategy, apparently in order to adapt changing and more complex environments. The results demonstrate that the relative importance of ecological processes changed during succession. Environmental filtering mainly dominated in early succession, and its strength gradually decreased as succession progressed. Both environmental filtering and competitive exclusion had important effects on community assembly in later succession. The assessment of the relative importance of ecological processes during succession could be biased if only based on one plant functional strategy
Nutrient Resorption and Stoichiometric Characteristics of Wuyi Rock Tea Cultivars
Get PDFNutrient resorption is an important strategy for plants to retain critical nutrients from senesced leaves and plays important roles in nutrient cycling and ecosystem productivity. As a main economic crop and soil and water conservation species, Wuyi Rock tea has been widely planted in Fujian Province, China. However, foliar nutrient resorptions of Wuyi Rock tea cultivars have not been well quantified. In this study, three Wuyi Rock tea cultivars (Wuyi Jingui, Wuyi Rougui, and Wuyi Shuixian) were selected in the Wuyishan National Soil and Water Conservation, Science and Technology Demonstration Park. Resorption efficiencies of nitrogen (NRE), phosphorus (PRE), and potassium (KRE) along with their stoichiometric characteristics were determined. PRE of the three tea cultivars was significantly higher than KRE and NRE, indicating that tea cultivars were P limited due to low P availability for the tea growth. With the exception of Wuyi Rougui, leaf N and P contents of the other two cultivars (Wuyi Jingui and Wuyi Shuixian) had strong homeostasis under the changing soil environments. Leaf thickness and specific leaf area were positively and significantly correlated with KRE, and total chlorophyll concentration was positively correlated with NRE, indicating that leaf functional traits can be used as indicators for nutrient resorption status. Wuyi Rock tea cultivars had strong adaptabilities to the environments and had high carbon sequestration capabilities; thus, they and could be introduced into nutrient-poor mountainous areas for both economic benefits and soil and water conservation
Design of an Artificial Intelligence Model Certification System for Untrained Operational Environments
No full textThe accuracy of Deep learning-based models for traffic state estimation (TSE), has been severely hampered by problems related to deficiencies in data availability, data collected during inclement weather conditions and the presence of noised data. Several scholars have asserted that certification of Machine Learning (ML) models using physics laws is an essential component in safety critical applications, however none of these studies have specifically examined the certification of Deep-Learning based models with physics laws to advance TSE. To expedite the application of Deep Learning models, it is critical to know whether a pre-trained AI model can be used in an unobserved operational environment with little or even no new data. However, it is often difficult to understand the black-box models learned by Deep Learning techniques from data. Considering that scientific knowledge is available for many engineering problems, this paper proposes a science-based certification methodology to sanity check whether the pre-trained data driven models can be used in untrained operational environments. This research demonstrates the benefit of certification of Deep Learning based models built using a small training synthetic dataset and certified by Lighthill-Whitham-Richards (LWR) law of traffic physics, depicted using the fundamental Greenshields’ diagram. This study certifies whether a TSE model trained in different traffic state conditions can be employed to predict a new environment that the model has not been trained on. The study also aims at improving interpretability and enhancing reliability of Deep Learning Models all being governed by the conservation law of traffic
Genome-Wide Association Study for Root System Architecture Traits in Field Soybean
No full textRoots are crucial for plant development, as they absorb water and nutrients from the soil and provide stability. Global warming can hinder root growth due to altered soil conditions, leading to drought-like effects and hampering plant growth. To address this challenge, Root System Architecture (RSA) traits, encompassing characteristics like total root length and number of lateral roots, need exploration. We examined seven RSA traits in 500 soybean accessions, growing seeds on germination and blue blotting papers, and assessing roots 21 days after transfer using RootNav2.0 software. Statistical analyses, including population structure, kinship, and principal component analysis, were conducted. We performed Genome-wide Association Studies (GWAS) using root phenotypic data and SNPs from the SoySNP50K iSelect SNP BeadChip with TASSEL 5.0 (MLM and GLM models) and FarmCPU. Both platforms identified 53 distinct SNPs, with 4 shared by GLM and MLM models, and the most on chromosome 13. For different traits, 8, 16, 5, 6, 1, 7, and 5 SNPs were found. We also developed CRISPR vectors with soybean-specific promoters for genome editing of root trait candidates, facilitating future research. These findings contribute to the discovery of key genes and QTLs for root system architecture, aiding in breeding resilient cultivars adaptable to changing climates
HBCU Health and Wellness Center: Perspective for Maintaining College Freshman Academic Success
No full textThis study aimed to explore the experiences and perceptions of college freshmen who maintained good academic standing of a GPA 2.0 and higher and used a Health and Wellness Workout Center at least once a week. The study used a qualitative research design, specifically a focus group, to gather in-depth information from participants. Participants were recruited through their participation in attending the Health and Wellness Center and were invited to participate in a focus group session. The focus group session was conducted using questions by the National Recreation and Wellness Association (NRWA), which were designed to explore the participants\u27 experiences and perceptions of using the Health and Wellness Workout Center and maintaining good academic standing of a GPA of 2.0. The data collected from the focus group was analyzed using thematic analysis, which involved identifying patterns and themes in the data. The study aimed to provide insights into the motivations, barriers, and strategies that college freshmen used to maintain a GPA 2.0 and higher and regularly use a Health and Wellness Workout Center. The findings of this study may help college health and wellness programs better understand the needs and experiences of their student population and may inform the development of interventions and programs that support academic success and physical activity
Biocontrol Evaluation and Benefits in Controlling Southern Blight in Pepper and Hemp
No full textSouthern blight disease caused by Sclerotia rolfsii is an economically important disease in pepper (Capsicum annuum L.) and hemp (Cannabis sativa L.) production in southeastern United States. Conducive environmental conditions for the disease include high temperatures of 30°C, pH 6.5, alternate light and darkness cycles of 12 hours. Southeastern United States, tropics and subtropic regions have favorable environment for this disease for growth and survival of resting structures allow the pathogen to survive long periods in soil. This disease is one of the problems facing industrial hemp production. Endophytes are known for symbiotic relationships with their hosts and occupy the same ecological niche as phytopathogens. Bacterial endophytes IMC8 (Bacillus thuringiensis), PRT (Bacillus subtilis) PSL (Bacillus amyloliquefaciens) and twelve other unidentified endophytes including two isolated from hemp (Hemp-1 and Hemp-2), were evaluated for potential in biocontrol of southern blight using laboratory bioassay dual cultures technique. Isolates IMC8, PRT, PSL Hemp-1 and Hemp-2 were evaluated for plant growth promotion and southern blight disease severity in hemp and pepper using pathogen infested soil in greenhouse and field. Results on laboratory assays showed that several endophytes including PSL, PRT, IMC-8, Hemp-1, and Hemp-2 significantly inhibited growth of Sclerotium rolfsii and exhibited great potential as biological control agents for southern blight disease management. Greenhouse and field studies showed PSL, PRT, IMC-8, Hemp-1, and Hemp-2 promoted hemp and sweet pepper plant growth and treated plants grown in soil infested with Sclerotium rolfsii in greenhouse and in field displayed growth promotion and reduced southern blight disease severity
Microbial Diversity and Antimicrobial-Resistant Profiles of Bacterial Communities in Goats and Sheep
No full textAnimal production farms are significant sources of antimicrobial-resistant pathogens and genes, but there\u27s a lack of understanding regarding antimicrobial resistance in small-scale farms. This study gathered 137 fecal samples from goat and sheep farms to investigate antimicrobial resistance and microbial diversity. Using a culture-dependent approach, the study identified prevalent bacteria such as E. coli (94.9%), S. aureus (91.3%), S. saprophyticus (81.0%), Shigella spp. (35.0%), and Salmonella spp. (3.0%). High resistance was observed against ampicillin (79.4%) and cephalothin (70.6%). Culture-independent results revealed that the dominant phyla in the fecal samples were Firmicutes, Bacteroidetes, Proteobacteria, and Spirochaetes. The α-diversity indices indicated similar microbial diversity regardless of sample type or farm location. However, β-diversity analysis demonstrated significant differences in microbial diversity by sample type and farm location, highlighting substantial variation in microbial community composition. The study underscores the need to explore further the prevalent microbes and resistant genes in these animal communities and their environments. Understanding the extent of resistant bacteria and microbial diversity in goat and sheep populations is vital for informed decision-making in livestock management, disease control, and sustainable agriculture. This knowledge is essential for enhancing the health, productivity, and well-being of these animals and ensuring the safety of food products derived from them