DEVELOPMENT AND VALIDATION OF REVERSE-PHASE HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY METHOD FOR SIMULTANEOUS ESTIMATION OF OLANZAPINE AND ARIPIPRAZOLE IN SYNTHETIC MIXTURES

Objective: A simple, rapid, accurate, precise, specific, and sensitive reverse-phase high-performance liquid chromatography (RP-HPLC) method has been developed and validated for simultaneous estimation of olanzapine (OLZ) and aripiprazole (APR) in synthetic mixtures. Methods: The stationary phase used for chromatographic separation was Phenomenex C18 column (250 mm × 4.6 mm i.d, particle size 5 μm) and mobile phase used for separation was methanol: Phosphate buffer (pH 3) taken in ratio of 75:25 %v/v. The flow rate was used 1.0 ml/min at room temperature and drugs detected at 240 nm with injection volume 20 μL. Results: The retention time for OLZ and APR was found to be 4.231 and 6.523 min, respectively. The linearity was performed using a concentration range of 0.5–3.0 for both drugs. The correlation coefficient was found to be 0.999 for OLZ and APR. The % purity of both the drug was found to be 98–102%. The proposed RP-HPLC method has been validated, according to International council on harmonization Q2 (B) guidelines. Conclusion: There was no interference of any diluents and excipients in the determination of drugs from synthetic mixture. Hence, the developed method can be used for routine quality control analysis

Supercritical fluid extraction of rice bran with adsorption on rice hull ash

Rice bran oil was extracted using environmentally-friendly supercritical carbon dioxide at varying conditions. Experimental treatments included pressure (27.6, 41.4 and 55.2 MPa), temperature (40 and 60 oC) and flow rates (25, 45 and 65 g/min) of supercritical carbon dioxide. Extracts collected at different time intervals during 4-hour extraction runs in a 3-L extractor were analyzed for oil yield and antioxidants. Normal-phase HPLC was used for analyzing the extract for important antioxidant compounds of oryzanol, tocopherols, tocotrienols. Silica rich rice hull ash adsorbent was also incorporated in combined extraction-adsorption experiments under similar supercritical fluid conditions. Supercritical extraction yields of rice bran oil and antioxidants were compared with 6 -hour Soxhlet extraction using petroleum ether solvent. Total oil extract yields for SFE (17.26-18.52 %) and experiments conducted with ash (17.35-18.99 %) for the extraction conditions of higher pressure (55.2 MPa) and flow rates (65 g/min) were comparable to the ether extractable oil yield (17.88 %). Extract yield significantly increased (p\u3c0.05) with an increase in pressure and flow rate. However, the temperature effect on extract yield was not significant. Antioxidant extraction significantly increased with increased pressure, but not with increased flow and temperature. These behaviors with pressure, flow and temperature were similar for oryzanol, tocopherols and tocotrienols. Rice hull ash adsorbent did not significantly affect oil yields, but did influence the antioxidants in the extract. A much greater ash adsorption effect for noted for oryzanol, which was different from the effect that was seen for of vitamin E components. A separate batch adsorption study carried out at different temperature (20, 30, 40 oC) for varied time intervals also showed similar adsorption behavior. Freundlich isotherms successfully described adsorption behavior of the antioxidant compounds in the batch study using rice bran oil-hexane miscella. Freundlich fitting parameters (k and 1/n) were used to plot Van’t Hoff- Arrhenius equations and calculate the change in enthalpy value (∆H) due to adsorption of antioxidants. Goto et al. (1993) model was applied to extraction yield data and successfully characterized extraction behavior. Values of partition coefficient K and mass transfer coefficient Kp were calculated and reported

Modeling and control of three-phase grid-connected PV inverters in the presence of grid faults

A two-stage photovoltaic grid-connected microgrid modeling approach is presented in this work. The purpose of the modeling is the behavior study of the microgrid during the low-voltage event on the grid. A complete mathematical model is discussed for each component of the system. The MPPT of the photovoltaic system is integrated with the boost controller to inject the constant current in the DC-link. The boost converter and the inverter control is implemented using the cascaded PI control. A dual second-order generalized integrator (DSOGI) method is implemented for the sequence extraction. The inverter controller is designed to meet the grid-code requirement of low-voltage ride through (LVRT) and reactive power injection. The simulation model is designed in a MATLAB/PLECS environment, and the controller design is validated by running a low-voltage event on the grid. To observe the interaction of a multiple PV system with the grid, a nonlinear average model of the two-stage grid-connected PV system was designed and validated against the switching model. A low voltage event on the grid was simulated to observe the impact on the multiple PV system. A power quality event of voltage dip during the unbalance voltage on the grid is presented. The implication of the ungrounded system during the low-voltage event is explained. In addition, the importance of grounding and the effect of the line impedance for the why-connected system is described in detail --Abstract, page iii

Petri net modeling and analysis of an FMS cell

Petri nets have evolved into a powerful tool for the modeling, analysis and design of asynchronous, concurrent systems. This thesis presents the modeling and analysis of a flexible manufacturing system (FMS) cell using Petri nets. In order to improve the productivity of such systems, the building of mathematical models is a crucial step. In this thesis, the theory and application of Petri nets are presented with emphasis on their application to the modeling and analysis of practical automated manufacturing systems. The theory of Petri nets includes their basic notation and properties. In order to illustrate how a Petri net with desirable properties can be modeled, this thesis describes the detailed modeling process for an FMS cell. During the process, top-down refinement, system decomposition, and modular composition ideas are used to achieve the hierarchy and preservation of important system properties. These properties include liveness, boundedness, and reversibility. This thesis also presents two illustrations showing the method adopted to model any manufacturing systems using ordinary Petri nets. The first example deals with a typical resource sharing problem and the second the modeling of Fanuc Machining Center at New Jersey Institute of Technology. Furthermore, this thesis presents the analysis of a timed Petri net for cycle time, system throughput and equipment utilization. The timed (deterministic) Petri net is first converted into an equivalent timed marked graph. Then the standard procedure to find the cycle time for marked graphs is applied. Secondly, stochastic Petri net is analyzed using SPNP software package for obtaining the system throughput and equipment utilization. This thesis is of significance in the sense that it provides industrial engineers and academic researchers with a comprehensive real-life example of applying Petri net theory to modeling and analysis of FMS cells. This will help them develop their own applications

Identification and Parsing of SQL Query Command by Implementation of JSON

In today’s world mobile devices have become a necessity for many people. These devices have ability to keep in touch with family members and business partners. It is also used to share information in real time.But some time people don’t like to input text on a small mobile device which may lead to error, compared to text input via full-sized keyboard on desktop computer system. In this paper we are going to present how SQL database query can be input using voice and technically parsed using JSON data storage. Here we use Pocketsphinx for Android and Google voice API to convert speech to text and create database query by processing text which return SQL query by processing JSON

Experimental studies to evaluate tensile and bond strength of Stainless-Steel Wire Mesh (SSWM)

Structural strengthening is vital to improve the load-carrying capacity partially or severely damaged Reinforced Concrete (RC) elements. Fiber Reinforced Polymers (FRPs) are widely used for strengthening purposes. In this study, use of Stainless-Steel Wire Mesh (SSWM) is explored, as FRPs are having limitations like high cost, less fire resistance, and brittle behavior. The experimental studies are conducted to evaluate the mechanical properties of the SSWM, to explore its feasibility as a strengthening material. Three different variants of SSWM i.e., 30×32, 40×32 and 50×34 is considered for the study. SSWM used in present study is a woven mesh made from stainless-steel wires manufactured in India. Important mechanical properties such as tensile strength and bond strength with concrete surface is experimentally evaluated in this study. Response of test specimens are evaluated with respect to ultimate load carrying capacity, corresponding deformations, rupture strain, crack formation and failure propagation. SSWM exhibits a tensile strength of 600-1000 MPa which is comparable to tensile strength of various types of fibers used for strengthening. Based on experimental studies, it is found that SSWM 40×32 performs the better in different aspect, so it can be a good alternative for strengthening of RC elements compared to other FRP materials

Thermally Activated Reversible Threshold Shifts in Yba\u3csub\u3e2\u3c/sub\u3eCu\u3csub\u3e3\u3c/sub\u3eO\u3csub\u3e7-δ\u3c/sub\u3e/Yttria-Stabilized Zirconia/Si Capacitors

Yba2Cu3O7-δ/yttria‐stabilized zirconia (YSZ)/silicon superconductor–insulator–semiconductor capacitors are characterized with capacitance‐voltage (C‐V) measurements at different gate‐voltage sweep rates and under bias‐temperature cycling. It is shown that ionic conduction in YSZ causes both hysteresis and stretch‐out in room‐temperature C‐V curves. A thermally activated process with an activation energy of about 39 meV in YSZ and/or at YSZ/Si interface is attributed to trapping/detrapping mechanisms in the SiOx interfacial layer between YSZ and Si. The negative mobile ions in YSZ can be moved by an applied electric field at room temperature and then ‘‘frozen’’ with decreasing temperature, giving rise to adjustable threshold voltages at low temperatures

Effect of diuretics on sodium, potassium and chloride levels- a cross sectional study

Background: Diuretics are one of the widely used class of drugs used in various cardiovascular and other disorders. However, they can cause various metabolic adverse effects, electrolyte imbalance being among important changes.Methods: A cross sectional study was conducted in which patients diagnosed with hypertension for at least one month were included. Over a period of 6 months patients were enrolled irrespective of whether they were taking diuretics or not. Demographic details, drug therapy and electrolyte levels were recorded in a proforma. Data was analyzed for difference in serum electrolyte levels between diuretic and nondiuretic groups as well as between different diuretic groups.Results: Out of total 177 participants, 71 were on diuretic therapy. There was significant difference in mean serum sodium (S. Na), potassium (S. K) and chlorine (S. Cl) levels between diuretic and nondiuretic groups (P<0.05). Hyponatremia, hypokalemia and hyperkalemia were observed. Thiazide diuretic group showed significantly greater hyponatremia compared to other diuretics (P=0.028). Hyperkalemia was observed in participants receiving K sparing diuretic or combination of loop and K sparing diuretics. Old age and number of comorbidities showed negative association with S. Na. Females had significantly more hyponatremia than male participants.Conclusions: The study confirms that diuretics cause various abnormalities in electrolytes namely Na and K levels. Old age, comorbidities and female sex are risk factors for hyponatremia

An evaluation of the promotional factors influencing general practitioners' prescribing behaviour, primarily the pharmaceutical representative.

Thesis (M.B.A.)-University of Natal, Pietermaritzburg, 2003.Generally the pharmaceutical industry operates in a heavily regulated and controlled environment. In South Africa, the regulations governing prescription drugs do not allow the pharmaceutical companies to advertise the prescription drugs directly to the consumers. As a consequence, the greater part of the marketing efforts of the pharmaceutical companies is directed at the medical practitioners, who occupy the crucial decision-making position for the prescription drugs. The study broadly investigates the relative influence of the various promotional factors that may influence the General Practitioner's choice of prescription drug and more specifically, focuses on the characteristics of the pharmaceutical sales representatives that may influence the prescribing behaviour of the General Practitioners. An area sample of 67 general practitioners in Pietermaritzburg, South Africa, was carried out. A total of 58 responses were analysed to determine the perceived influence of various factors on the GPs' choice of new and existing prescription drugs. A specific attempt was made to determine the key influential factors with respect to the promotion by the pharmaceutical representatives and GPs' appreciation of basic statistics used in the presentations by the pharmaceutical representatives