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The Effects of Fertilizer Rate on the Growth of Egyptian Spinach in a Greenhouse
Get PDFEgyptian spinach (Corchorus olitorius, L.) is an annual herb and a popular vegetable grown in the dry, semi-arid and humid regions of Africa. It belongs to the American basswood family and is very nutritious, and known to have medicinal properties as well. Introducing Egyptian spinach as a specialty crop in Texas requires examining and determining the best cultural practices needed for its successful production. The objective of this study was to determine the effects of three nitrogen fertilizer rates on the growth of Egyptian spinach grown under greenhouse conditions. We hypothesized that the yield of Egyptian spinach will increase with increasing nitrogen fertilizer rate. Seedlings of equal sizes were transplanted six weeks after planting into 15 cm plastic containers with Sunshine Professional Growing Mix. The plants were fertilized weekly with a micronutrient (i.e. boron, copper, iron, manganese, molybdenum and zinc) containing fertilizer, All Purpose MiracleGro fertilizer [24-8-16], (Scotts Miracle-Gro Products Inc., Marysville, OH) at 94, 188, and 376 kg N ha-1 for about 4.5 months. Weekly harvesting of the fresh shoots and weighing commenced nine weeks after transplanting and continued for approximately nine additional weeks. At the conclusion of the study, the results showed that the 94 kg N ha-1 rate of MiracleGro provided a significantly higher shoot biomass yield than the other treatments. The results imply that fertilizing Egyptian spinach at the 94 kg N ha-1 fertilizer rate is the best way to optimize yields under similar growing conditions. The results also suggest that optimizing field production of Egyptian spinach may require supplementing soils with micronutrients
Electrostatic potential of a uniformly charged square plate at an arbitrary point in space
No full textWe calculate exactly in closed analytic form the Coulomb electrostatic potential created by a uniformly charged square plate at an arbitrary point in space. We apply a suitable transformation of variables that allows us to obtain a simple presentation of the Coulomb electrostatic potential in one-dimensional integral form. The final closed form analytic expression of the electrostatic potential is obtained after completing the calculation of the resulting one-dimensional integrals. The exact analytic formula that we derive reflects the symmetry of the square and is easy to implement. The exact analytical result reported in this work represents a much desirable compact, symmetric and easy to implement expression for the Coulomb electrostatic potential created by a uniformly charged square plate at an arbitrary point in space
Influence of community-level factors on relation between community resilience and posttraumatic growth.
No full textThe current study aimed at exploring the influence of individual- and community-level factors on posttraumatic growth (PTG) after Hurricane Harvey and whether the community-level factors moderate the relation between perceived community resilience and PTG. Final participants were 415 adults who reported directly experiencing Hurricane Harvey, which made landfall on August 26, 2017. Data collection occurred approximately 16 months after the hurricane. Perceived community resilience and household income were significantly associated with PTG. There was a marginally significant cross-level interaction effect between perceived community resilience and median household income on PTG. The current study raises an important implication of economic development on facilitating PTG. (PsycInfo Database Record (c) 2020 APA, all rights reserved
Dynamic Optimal Control for Multi-chemotherapy Treatment of Dual Listeriosis Infection in Human and Animal Population
Get PDFFollowing the rising cases of high hospitalization versa-vise incessant fatality rates and the close affinity of listeriosis with HIV/AIDS infection, which often emanates from food-borne pathogens associated with listeria monocytogenes infection, this present paper seek and formulated as penultimate model, an 8-Dimensional classical mathematical Equations which directly accounted for the biological interplay of dual listeriosis virions with dual set of population (human and animals). The model was studied under multiple chemotherapies (trimethoprim-sulphamethoxazole with a combination of penicillin or ampicillin and/or gentamicin). Using ODE’s, the positivity and boundedness of system solutions was investigated with model presented as an optimal control problem. In the analysis that follows, the study explored classical Pontryagin’s Maximum Principle with which the model optimality control system as well as existence and uniqueness of the control system were established. In correlating the derived model with clinical implications, numerical validity of the model was conducted. Results indicated that under cogent and adherent to specify multiple chemotherapies, maximal recovery of both human and animal infected population was tremendously achieved with consequent rapid decline to near zero infection growth. The study therefore suggests further articulation of more chemotherapies and early application at onset of infection for a visible elimination of listeriosis infection
Variants of Meir-Keeler Fixed Point Theorem And Applications of Soft Set-Valued Maps
Get PDFIn this paper, we prove a Meir-Keeler type common fixed point theorem for two mappings for which the range set of the first one is a family of soft sets, called soft set-valued map and the second is a point-to-point mapping. In addition, it is also shown that under some suitable conditions, a soft set-valued map admits a selection having a unique fixed point. In support of the obtained result, nontrivial examples are provided. The novelty of the presented idea herein is that it extends the Meir-Keeler fixed point theorem and the theory of selections for multivalued mappings from the case of crisp mappings to the frame of soft set-valued maps. Finally, an application of soft setvalued maps in decision making problems is considered
A Comparative Study of Shehu Variational Iteration Method and Shehu Decomposition Method for Solving Nonlinear Caputo Time-Fractional Wave-like Equations with Variable Coefficients
Get PDFIn this paper, a comparative study between two different methods for solving nonlinear Caputo time-fractional wave-like equations with variable coefficients is conducted. These two methods are called the Shehu variational iteration method (SVIM) and the Shehu decomposition method (SDM). To illustrate the efficiency and accuracy of the proposed methods, three different numerical examples are presented. The results obtained show that the two methods are powerful and efficient methods which both give approximations of higher accuracy and closed form solutions if existing. However, the SVIM has an advantage over SDM that it solves the nonlinear problems without using the Adomian polynomials. Furthermore, the SVIM enables us to overcome the difficulties arising in identifying the general Lagrange multiplier and it may be considered as an added advantage of this technique over the SDM
On the Asymptotic Stability of a Nonlinear Fractional-order System with Multiple Variable Delays
Get PDFIn this paper, we consider a nonlinear differential system of fractional-order with multiple variable delays. We investigate asymptotic stability of zero solution of the considered system. We prove a new result, which includes sufficient conditions, on the subject by means of a suitable Lyapunov functional. An example with numerical simulation of its solutions is given to illustrate that the proposed method is flexible and efficient in terms of computation and to demonstrate the feasibility of established conditions by MATLAB-Simulink
COVID-19 and the improvement of the global air quality: The bright side of a pandemic
No full textThe objective of this investigation is to study the impacts of the global response to COVID-19 on air pollution and air quality changes in major cities across the globe over the past few months. Air quality data (NO2, CO, PM2.5, and O3) were downloaded from the World Air Quality Index project for the January 2019–April 2020 period. Results show a significant reduction in the levels of 2020 NO2, CO, and PM2.5 compared to their levels in 2019. These reductions were as high as 63% (Wuhan, China), 61% (Lima, Peru), and 61% (Berlin, Germany), in NO2, CO, and PM2.5 levels, respectively. In contrast, 2020 O3 levels increased substantially, as high as 86% (Milan, Italy), in an apparent response to the decrease in titration by nitrogen monoxide and its derivatives. Significant differences in the weather conditions across the globe do not seem to impact this air quality improvement trend. Will this trend in the reduction in most air pollutants to unprecedented levels continue in the next few weeks or even months? The response to this and other questions will depend on the future global economic and environmental policies
Pd/C catalyzed room-temperature, atmospheric pressure hydrogenation of furanic bio-oils from acidic ionic liquid catalyzed liquefaction of biomass in acetone
No full textFuranic bio-oils were produced from liquefaction of corn cobs and switchgrass using 1-(3-propylsulfonic)-3-methylimidazolium chloride catalyst in acetone at 120 °C, 5 h. The biomass conversions to bio-oils for corn cobs and switchgrass were 43.8 ± 1.9 and 40.2 ± 1.4% (w/w) respectively. The bio-oils were then catalytically hydrogenated in water: methanol 3:1 (v/v) at room-temperature and atmospheric pressure using 5% Pd-C catalyst to give hydrogenated bio-oils and analyzed using GC–MS to identify the products. GC–MS analysis revealed that majority of the products in hydrogenated bio-oils is C4-C17 alcohols, ethers and furans. A total of 64 products were observed in GC–MS and 61 were identified with the use of mass spectroscopy. These products are arising from the partial reduction as well as deoxygenation of biomass derived furan aldehyde - acetone cross aldol products and acetone self condensation products. In addition, NMR analysis was used to quantify the effect of catalytic hydrogenation. 1H NMR spectra peak integration for the alkene-furan region (6.0–8.0 ppm) showed reductions of 19.0 to 1.8% and 19.1 to 2.6% due to the catalytic hydrogenation of bio-oils from corn cobs and switchgrass, confirming the effect of Pd-C catalyzed, 1 Atm., room temperature hydrogenation
Effect of porosity on unsteady MHD convection flow Past a moving vertical plate with ramped wall temperature
Get PDFThe unsteady MHD convective flow of an electrically conducting fluid embedded in a porous medium along moving infinite vertical plate with ramped wall temperature and radiation in a rotating system is investigated here. The fluid taken is incompressible and viscous. The governing PDE’s of the model are solved by using integral transform method. The analytical solutions for the velocity, concentration and temperature are obtained. The expressions for skin friction, rate of mass transfer and heat transfer near the plate are obtained. The effects of various parameters like porosity of the medium, magnetic field, Soret number, thermal radiation, rotation, radiation and Hall current on the flow field are discussed. It is observed that velocity increases with the increase in the porosity parameter K. It reveals that a porous medium having large permeability supports the movement of the fluid in the system. Also, it is noticed that Hall parameter reduces the resistive effect of the applied magnetic field. Such a study assumes importance because both rotation and Hall current induce secondary flow in the flow-field. The results of the research may be useful in many industrial applications