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Panther - February 2015 - Vol. XCV No. 4
Get PDFhttps://digitalcommons.pvamu.edu/pv-panther-newspapers/1407/thumbnail.jp
Panther - November 2015 - Vol. XCVI, NO.8
Get PDFhttps://digitalcommons.pvamu.edu/pv-panther-newspapers/1918/thumbnail.jp
Determination of withdrawal time for oxytetracycline in different types of goats for milk consumption
No full textAntibiotics are widely used in animal husbandry and the presence of antibiotics in milk is a health hazard. The objective of this study was to determine residual amounts of oxytetracycline in fresh, aged, and pasteurized milk of 3 breeds of goats using HPLC analysis. It was also essential to determine the safe withdrawal period of oxytetracycline in lactating goats. The quantitative results obtained using the HPLC system were compared with the tolerance limit of oxytetracycline in milk in the United States. Fifteen milking does, 5 Nubians, 5 Alpines, and 5 LaManchas were randomly selected from the milking herd at the International Goat Research Center at Prairie View A&M University. A simple sample preparation and isocratic HPLC method using ultraviolet detection was used for analysis of milk samples. The HPLC results indicated that the withdrawal period of oxytetracycline in treated Alpine does was 82. h (7 milking), whereas for Nubian does the period was 58. h (5 milking), and for LaManchas the period was 72. h (6 milking) after drug administration. The overall withdrawal period for all the treated goats of 3 breeds was 72. h. Although these results indicated that the depletion rate of this antibiotic was faster in goats than the reported data for cows, the 96-h withdrawal period that is currently used for lactating cows is still necessary for these 3 breeds of goats. Additionally, our results indicated that oxytetracycline is not stable in goat milk at refrigeration temperature or during pasteurization and will decrease significantly
Poly(Caprolactone)/chitosan-based scaffold using freeze drying technique for bone tissue engineering application
No full textHighly porous 3Dimensional (3D) scaffold becomes a promising alternative approach for bone repairing. The aim of this research was to fabricate Polycaprolactone (PCL) blended with chitosan 3D-porous scaffold with improved hydrophilic behavior for bone tissue engineering applications. An effective technique, freeze drying technique was chosen to produce the sponge-like porous 3D scaffolds of 10%w/v pure PCL and 12%w/v blended PCL/Chitosan. Several characterizations such as Scanning Electron Microscope (SEM) and Attenuated Total Reflectance (ATR)-Fourier Transform Infrared (FTIR) were carried out to examine the morphologies and the chemical bonding of the scaffolds while water contact angle and water uptake experiment were done to investigate the hydrophilicity of the fabricated scaffolds. SEM observation revealed that the pure PCL and the blended PCL/Chitosan scaffolds had highly porous structure with average pore size of 73.6 μm and 74.9 μm which is in the optimum range of pore size for bone ingrowth. The results of ATR-FTIR showed that chitosan was successfully blended into PCL scaffold. The PCL/Chitosan blended scaffold fabricated in this study possessed homogeneous porous structures with improved hydrophilic properties. This PCL/Chitosan blended scaffold may have a high potential for the bone tissue engineering application
Concise presentation of the Coulomb electrostatic potential of a uniformly charged cube
No full textWe use a novel method to calculate in closed form the Coulomb electrostatic potential created by a uniformly charged cube at an arbitrary point in space. We apply a suitable transformation of variables that allows us to obtain a simple presentation of the electrostatic potential in one-dimensional integral form. The final concise closed form expression of the Coulomb electrostatic potential of the uniformly charged cube is obtained after completing the calculation of the resulting one-dimensional integrals. Such integrals consist of combinations of products of error functions and power functions that can be solved exactly despite their intimidating appearance. The exact analytic formula for the Coulomb electrostatic potential that we derive reflects the symmetry of the cube and is easy to implement. We illustrate its use by calculating the exact values of the electrostatic potential at some points of symmetry such as the center of cube, center of face of cube, center of edge of cube and corner of cube
Panther - April 2015- Vol. XCV, NO.7
Get PDFhttps://digitalcommons.pvamu.edu/pv-panther-newspapers/1917/thumbnail.jp
E-super vertex magic labelling of graphs and some open problems
Get PDFLet G be a finite graph with p vertices and q edges. A vertex magic total labelling is a bijection from the union of the vertex set and the edge set to the consecutive integers 1, 2, 3, . . . , p + q with the property that for every u in the vertex set, the sum of the label of u and the label of the edges incident with u is equal to k for some constant k. Such a labelling is E-super, if the labels of the edge set is the set {1, 2, 3, . . . , q }. A graph G is called E-super vertex magic, if it admits an E-super vertex magic labelling. In this paper, we establish an E-super vertex magic labelling of some classes of graphs and provide some open problems related to it
A Note on an M/M/s Queueing System with two Reconnect and two Redial Orbits
Get PDFA queueing system with two reconnect orbits, two redial (retrial) orbits, s servers and two independent Poisson streams of customers is considered. An arriving customer of type i, i = 1, 2 is handled by an available server, if there is any; otherwise, he waits in an infinite buffer queue. A waiting customer of type i who did not get connected to a server will lose his patience and abandon after an exponentially distributed amount of time, the abandoned one may leave the system (lost customer) or move into one of the redial orbits, from which he makes a new attempt to reach the primary queue, and when a customer finishes his conversation with a server, he may comeback to the system, to one of the reconnect orbits where he will wait for another service. In this paper, a fluid model is used to derive a first order approximation for the number of customers in the redial and reconnect orbits in the heavy traffic. The fluid limit of such a model is a unique solution to a system of three differential equations
A Hybrid Variational Iteration Method for Blasius Equation
Get PDFThe objective of this paper is to present the hybrid variational iteration method. The proposed algorithm is based on the combination of variational iteration and shooting methods. In the proposed algorithm the entire domain is divided into subintervals to establish the accuracy and convergence of the approximate solution. It is found that in each subinterval a three term approximate solution using variational iteration method is sufficient. The proposed hybrid variational iteration method offers not only numerical values, but also closed form analytic solutions in each subinterval. The method is implemented using an example of the Blasius equation. The results show that a hybrid variational iteration method is a powerful technique for solving nonlinear problems
Solution of fractional Drinfeld-Sokolov-Wilson equation using Homotopy perturbation transform method
Get PDFIn this article, the approximate solutions of the non-linear Drinfeld-Sokolov-Wilson equation with fractional time derivative have been obtained. The fractional derivative is described in the Caputo sense. He’s polynomial is used to tackle the nonlinearity which arise in our considered problems. A time fractional nonlinear partial differential equation has been computed numerically. The numerical procedures illustrate the effectiveness and reliability of the method. Effects of fractional order time derivatives on the solutions for different particular cases are presented through graphs