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(R1978) Heated Laminar Vertical Jet of Psudoplastic Fluids-Against Gravity
Get PDFA heated laminar jet of Pseudo-plastic fluid flowing vertically upwards from a long narrow slit into a region of the same fluid which is at a rest and at a uniform temperature is considered. The governing non-linear Partial differential equations (PDEs) for the defined flow problem are transformed into non-linear ordinary differential equations using the effective similarity technique-one parameter deductive group theory method. The obtained non-linear coupled Ordinary differential equations are solved and the results are presented by graphs. The effect of the Prandtl number and Grashof number on the velocity and temperature of the jet flow is discussed. Also, a detailed discussion of some interesting applications of the vertical jet flow of pseudoplastic fluids in different fields of engineering and geophysics are provided
(R1522) Modelling the Influence of Desertic Aerosols on the Transmission Dynamics of Neisseria Meningitidis Serogroup A
Get PDFThis paper assesses the role of desert aerosols and vaccine on the transmission dynamics of Neisseria Meningitis serogroup A (NmA). It is biologically well-documented that the inhalation of aerosol dust and its presence in the nasal cavity weakens the nasopharyngeal mucosa by damaging the mucosal barrier and inhibiting the mucosal immune defenses of susceptible and vaccinated individuals. We address the latter by proposing and analyzing a mathematical model for the dynamics of NmA that specifically accounts for the fast progression of susceptible and vaccinated individuals to the invasive stage of the disease. We compute the basic reproduction number and use it to investigate the existence and stability of equilibria. In this regard, we prove that the model undergoes a backward bifurcation phenomenon. We highlight the detrimental impact of aerosol dust by showing that its inhalation augments the reproduction number and enhances the endemic level of NmA.We also highlight the favorable role of vaccine in eliminating the disease when it has a high level of efficacy and is used to protect a large proportion of the population. The theoretical results are supported and illustrated by numerical simulations
(R1960) Connectedness and Compactness in Fuzzy Nano Topological Spaces via Fuzzy Nano Z Open Sets
Get PDFIn this paper, we study the notion of fuzzy nano Z connected spaces, fuzzy nano Z disconnected spaces, fuzzy nano Z compact spaces and fuzzy nano Z separated sets in fuzzy nano topological spaces. We also give some properties and theorems of such concepts with connectedness and compactness in fuzzy nano topological spaces
(R1974) A Multi Server Markovian Working Vacation Queue With Server State Dependent Rates and with Partial Breakdown
Get PDFIn this article, we consider an M/M/C queue in which the arrival rate and service rate depends on the state of the system. In addition, the servers takes working vacation and the system may breakdown. Whenever breakdown takes place, the repair process immediately commences. During the repair period the customers are given service in a reduced service rate. Based on the vacation termination point, two models have been defined. The steady state probability vector of the number of customers in the queue and the stability condition are obtained using Matrix-Geometric method. The stationary waiting time distributions have been obtained. Some illustrative examples are also provided
Sperm proteins ODF2 and PAWP as markers of fertility in breeding bulls
No full textLow fertility is the single most important factor limiting livestock reproductive performance, adversely affecting the cattle industry and causing millions of dollars of economic loss. In the livestock industry, male fertility is of crucial importance for the reproductive performance of livestock. However, there is a lack of reliable biomarkers to predict bull fertility in artificial insemination service. The objective of this study was to identify sperm proteins as biomarkers for bull fertility. To discover candidate sperm quality biomarkers, sperm proteome profiling was conducted in extreme high- and extreme low-fertile bulls selected from a pool of 1000 AI sires with varied fertility. Thirty-two differentially expressed proteins were identified. Among them, high levels of sperm outer dense fiber of sperm tails 2 (ODF2) and post-acrosomal assembly of sperm head protein (PAWP/WBP2NL) represented the most extreme differences in quantity between high- and low-fertility bulls. Protein immunodetection and flow cytometry used to validate these putative fertility markers in a combined cohort of 154 AI sires. Both ODF2 and PAWP correlated significantly with fertility. In conclusion, ODF2 and PAWP can be used to assess semen quality and predict sire fertility
(R1503) Numerical Ultimate Survival Probabilities in an Insurance Portfolio Compounded by Risky Investments
Get PDFProbability of ultimate survival is one of the central problems in insurance because it is a management tool that may be used to check on the solvency levels of the insurer. In this article, we numerically compute this probability for an insurer whose portfolio is compounded by investments arising from a risky asset. The uncertainty in the celebrated Cramér-Lundberg model is provided by a standard Brownian motion that is independent of the standard Brownian motion in the model for the risky asset. We apply an order four Block-by-block method in conjunction with the Simpson rule to solve the resulting Volterra integral equation of the second kind. The ultimate survival probability is arrived at by taking a linear combination of some two solutions to the Volterra equations. The several numerical examples show that the results are accurate and reliable. The method performs well even when the net profit condition is violated
(R1517) Asymptotical Stability of Riemann-Liouville Fractional Neutral Systems with Multiple Time-varying Delays
Get PDFIn this manuscript, we investigate the asymptotical stability of solutions of Riemann-Liouville fractional neutral systems associated to multiple time-varying delays. Then, we use the linear matrix inequality (LMI) and the Lyapunov-Krasovskii method to obtain sufficient conditions for the asymptotical stability of solutions of the system when the given delays are time dependent and one of them is unbounded. Finally, we present some examples to indicate the efficacy of the consequences obtained
EKOI Culture of Arts from southeastern region of Nigeria and parts of Cameroon- (Janusform Helmet Mask)
No full textJanusform helmet mask from the Ekoi culture of Nigeria. The Janusform of the mask, crowned with a headdress of feathers is worn to celebrate the return of its most recent initiates to village life.https://digitalcommons.pvamu.edu/african-sculptures-and-masks/1018/thumbnail.jp