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The Black Church and Public Health: A Key Partnership for Theory Driven COVID-19 Recovery Efforts
Get PDFThe COVID-19 epidemic has negatively impacted the Black community in the United States. Despite current disease mitigation efforts, work is still needed to ensure that Black individuals living in the United States understand their risks regarding COVID-19 infection whether vaccinated or unvaccinated. Thus, the current article posits that the Black church, in concert with public health practitioners, is a venue through which theoretically based health messages should be designed and disseminated regarding COVID-19 recovery efforts. The Health Belief Model and the Harm Reduction approach are posed as theoretical frameworks to facilitate the design of such messages
Influence of Citrate and Phosphate on the Adsorption of Adenosine-5′-Monophosphate at the Hematite Water Interface
Get PDFNucleic acid derived organic phosphorus (Po) is an important source of plant available P when degraded to inorganic phosphate (P(V)i). It is known that when nucleic acids or components are adsorbed on mineral surfaces, the enzymatic degradation is hindered or delayed. Thus, understanding adsorption/desorption mechanisms of nucleic acids and their derivatives are key to assess the biogeochemical pathways of Po cycling. Here we report adsorption mechanisms of adenosine-5′-monophosphate (AMP) on hematite, a common iron oxide mineral, under various solution properties using macroscopic and in situ attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopic probes. The effects of citrate, mimicking organic acids from roots exudates, and the influence of P(V)i, representing inorganic fertilizer application, were also evaluated on the release of adsorbed AMP under various solution properties. The results suggested that AMP adsorbed with the hematite surface via the phosphate moiety, N7 atom and the π electron systems of the adenine moiety. The presence of citrate significantly decreased the AMP adsorption, which was also corroborated by the negative phosphate IR bands in the results of AMP and citrate competitive adsorption experiments monitored by in situ ATR-FTIR probe. Like citrate, P(V)i also reduced AMP adsorption on hematite. Our findings suggest a potential novel pathway of nucleic acid derived Po cycling in the soil environment
Type of Stress Induces Differential Responses in Acer rubrum (Red Maple), but Induced Responses Have No Effect on Herbivorous Pests
Get PDFPlants thrive in dynamic environments requiring adaptive strategies in response to environmental stressors. Furthermore, insect herbivores may be attracted or deterred by the expression of these traits. This study examines growth, physiological, and phytochemical adaptations of maple trees in response to stressors and how these stressors effect herbivore feeding behavior within an agricultural production system. Agricultural systems are unique because plants experience environmental stressors unique to production such as herbicide sprays and girdling. Using four environmental stressors commonly observed in agricultural production (control, mechanical defoliation, chemical defoliation, and girdling), applied to two cultivars of red maple (Acer rubrum, ‘Brandywine’ and ‘Franksred’), this study analyzed differentiation of expressed traits in a production system. Responses varied depending on cultivar and stress treatment but had no effect on insect herbivore behavior. Understanding the ecological interactions within these systems will provide information for better plant production and pest management recommendations
Incommensurate conformable-type three-dimensional Lotka–Volterramodel: discretization, stability, and bifurcation
Get PDFThe classic Lotka–Volterra model is a two-dimensional system of differential equations used to model population dynamics among two-species: a predator and its prey. In this article, we consider a modified three-dimensional fractional-order Lotka–Volterra system that models population dynamics among three-species: a predator, an omnivore and their mutual prey. Biologically speaking, population models with a discrete and continuous structure often provide richer dynamics than either discrete or continuous models, so we first discretize the model while keeping one time-continuous dependent variable in each equation. Then, we analyze the stability and bifurcation near the equilibria. The results demonstrated that the dynamic behaviors of the discretized model are sensitive to the fractional-order parameter and discretization parameter. Finally, numerical simulations are performed to explain and validate the findings, and the maximum Lyapunov exponents is computed to confirm the presence of chaotic behavior in the studied mode
Responses of soil heterotrophic respiration and microbial biomass to organic and conventional production systems
Get PDFThe effects of organic and conventional production systems on crop productivity have been greatly explored, but their effects on soil microbial processes were often neglected. A comparative field study of organic and conventional production systems was conducted at the Tennessee State University research farm to determine soil heterotrophic respiration and microbial biomass carbon. Leafy green vegetables were grown in a conventional production system in an open field, and they were grown in an organic production system, using three different row covers (agribon cloth, insect net, and plastic), and in an open field. Soil samples (0-15cm) were collected from the two production systems. Soil heterotrophic respiration rate (RH), microbial biomass carbon (MBC), and biomass-specific heterotrophic respiration rate (the inverse is used as a proxy for microbial carbon use efficiency) were quantified. The results showed that the conventional production system significantly increased RH relative to the organic system. Organic production system, however, significantly enhanced MBC and reduced biomass-specific respiration rate indicating an increase in carbon use efficiency. Although MBC remained unchanged among the row covers, insect net increased RH and biomass-specific heterotrophic respiration rate. Our results suggest that the organic production system not only promoted soil microbial abundance but also limited soil heterotrophic respiration to the atmosphere governed by the elevated carbon use efficiency
The California Legacy Survey. III. On the Shoulders of (Some) Giants: The Relationship between Inner Small Planets and Outer Massive Planets
Get PDFWe use a high-precision radial velocity survey of FGKM stars to study the conditional occurrence of two classes of planets: close-in small planets (0.023–1 au, 2–30 M⊕) and distant giant planets (0.23–10 au, 30–6000 M⊕). We find that 41 %13 15 - + of systems with a close-in, small planet also host an outer giant, compared to 17.6 %1.9 2.4 - + for stars irrespective of small planet presence. This implies that small planet hosts may be enhanced in outer giant occurrences compared to all stars with 1.7σ significance. Conversely, we estimate that 42 %13 17 - + of cold giant hosts also host an inner small planet, compared to 27.6 %4.8 5.8 - + of stars irrespective of cold giant presence. We also find that more massive and close-in giant planets are not associated with small inner planets. Specifically, our sample indicates that small planets are less likely to have outer giant companions more massive than approximately 120 M⊕ and within 0.3–3 au, than to have less massive or more distant giant companions, with ∼2.2σ confidence. This implies that massive gas giants within 0.3–3 au may suppress inner small planet formation. Additionally, we compare the host-star metallicity distributions for systems with only small planets and those with both small planets and cold giants. In agreement with previous studies, we find that stars in our survey that only host small planets have a metallicity distribution that is consistent with the broader solar-metallicity-median sample, while stars that host both small planets and gas giants are distinctly metal rich with ∼2.3σ confidence
Exploring the Audio Engineering Technology Faculty Teaching Experience during the COVID-19 Pandemic
No full textIn fall 2020, the COVID-19 pandemic created a sudden transition to emergency remote teaching for faculty and students in Audio Engineering Technology (AET) degree programs. This qualitative study explored the experience of AET faculty who taught online using synchronous and asynchronous video during both spring and fall 2020. This study uses the Community of Inquiry (COI) theoretical framework to explore the teaching strategies of AET faculty in response to the pandemic. Qualitative data analysis was performed and responses were interpreted through the three COI elements of teaching presence, social presence, and cognitive presence. An online survey was conducted with 25 faculty, and follow-up focus groups interviews were conducted. These focus group meetings provided additional details about the teaching strategies faculty used during this shift to emergency remote teaching. The results of this study add to the body of knowledge around creating communities of inquiry in AET courses. This study also provides findings, recommendations for future research, and important implications for AET departments and faculty who want to build effective communities of inquiry for their courses, whether in-person or online
Application of Synthetic Peptide CEP1 Increases Nutrient Uptake Rates Along Plant Roots
Get PDFThe root system of a plant provides vital functions including resource uptake, storage, and anchorage in soil. The uptake of macro-nutrients like nitrogen (N), phosphorus (P), potassium (K), and sulphur (S) from the soil is critical for plant growth and development. Small signaling peptide (SSP) hormones are best known as potent regulators of plant growth and development with a few also known to have specialized roles in macronutrient utilization. Here we describe a high throughput phenotyping platform for testing SSP effects on root uptake of multiple nutrients. The SSP, CEP1 (C-TERMINALLY ENCODED PEPTIDE) enhanced nitrate uptake rate per unit root length in Medicago truncatula plants deprived of N in the high-affinity transport range. Single structural variants of M. truncatula and Arabidopsis thaliana specific CEP1 peptides, MtCEP1D1:hyp4,11 and AtCEP1:hyp4,11, enhanced uptake not only of nitrate, but also phosphate and sulfate in both model plant species. Transcriptome analysis of Medicago roots treated with different MtCEP1 encoded peptide domains revealed that hundreds of genes respond to these peptides, including several nitrate transporters and a sulfate transporter that may mediate the uptake of these macronutrients downstream of CEP1 signaling. Likewise, several putative signaling pathway genes including LEUCINE-RICH REPEAT RECPTOR-LIKE KINASES and Myb domain containing transcription factors, were induced in roots by CEP1 treatment. Thus, a scalable method has been developed for screening synthetic peptides of potential use in agriculture, with CEP1 shown to be one such peptide
