Optimal operational policies in batch distillation

Imperial Users onl

DRUG UTILISATION EVALUATION OF ANTIHYPERTENSIVES IN GERIATRIC PATIENTS IN A TERTIARY CARE HOSPITAL

Objective: Hypertension is a leading contributor to the global burden of cardiovascular morbidity and mortality. The main objective of the present study was to assess the drug utilization patterns of antihypertensives in geriatric patients in a teaching hospital. Methods: A Single centre Prospective Observational study was carried out for a period of three months in an out-patient department of Owaisi Hospital & Research Centre. Elderly patients who have been diagnosed with hypertension as per JNC-7 guidelines and patients receiving or prescribed with antihypertensive drugs were included. Results: A total of 100 prescriptions were analyzed during the three month study period. 72% of the patients were in the age group of 65-67 years and this was found to be higher in men 68%. During the study period 80% of the patients were Pre-Hypertensive systolic (80-89 mmHg) and Diastolic (120-139 mmHg) followed by Stage-I Hypertension and Stage-II Hypertension. The most common drug classes involved in the study was Calcium Channel Blockers 37% followed by Angiotensin II receptor antagonists 21% and the most commonly prescribed drugs in the study population were Amlodipine 37%, Losartan 11% and Telmisartan 10%. The most common anti-hypertensive fixed dose combination therapy involved in the study was Telmisartan + Hydrochlorothiazide 15% and most common two drug combination therapy involved in the study was Amlodipine + Atenolol 7% followed by Metoprolol + Amlodipine 1%. Conclusion: Our study shows that the most commonly prescribed drug classes involved were Calcium Channel Blockers followed by Angiotensin II receptor antagonists and the anti-hypertensive drug combinations among hypertensive patients were considerable and this practice positively impacted on the overall blood pressure control

Design of cyclic prefix characteristic-based OFDM system for WiMAX technology

Worldwide interoperability for microwave access (WiMAX) offers the wireless connectivity using orthogonal frequency division multiplexing (OFDM) modulation is a proficient wireless technology that capacities high-speed data transmission facilities. The existing WiMAX techniques have the problem of increase in inter-symbol interference (ISI) and bit error rate (BER) at reduced power spectrum that degrades the performance of WiMAX system due to high data rate transmission. The utilization of different adaptive modulation techniques seen as a potential solution to reduce the ISI and BER for high data rate transmission. In this paper, OFDM is adapted using advanced modulation technique for WiMAX system. The technique proposes the cyclic prefix (CP) is utilized that include supplementary bits at the stage of the transmitter. The proposed technique offers minimization of ISI and improvement in BER. It is defined that performance of the existing CP system is equated with the designed single cyclic prefix (SCP) and double cyclic prefix (DCP) and non-cyclic prefix (NCP). BER, probability of error, and power spectral density are utilized to analyse the performance of the designed system. The OFDM based SCP and DCP and NCP for WiMAX are demonstrated for modulation techniques such as; QPSK, BPSK, and QAM. It is determined that BPSK has the smallest BER when compared to QPSK, 16-QAM, and 64-QAM modulations. It is also demonstrated that QPSK is also very competent, however, it has a higher BER as compared to BPSK modulation. It is also observed that 16-QAM and 64-QAM are less efficient in terms of BER compared to QPSK and BPKS modulations. 64-QAM offers the high data rates, and due to high SNR ratio. The designed system is tested for under AWGN and Rayleigh fading channel, and effect power spectral density of signal to noise ratio on OFDM for rayleigh fading channel are demonstrated for SCP and DCP and NCP. It is determined that the OFDM transmitter with proposed DCP for random signals is efficiently reducing the BER and ISI for WiMAX system

Expectations Versus Realities Of Higher Education: Gap Analysis And University Service Examination

The university education providers are waking to student recruitment challenges, competition, and the realities of marketing. With these changes, a related and equally important issue has emerged; that is, the student service quality and evaluating of the educational encounter. Using university services as the primary study setting, the study explores the concept of university services quality and its evaluation from both the university provider and student perspectives. Gap analysis is used as an appropriate approach for examining the similarities and differences in expectations of the university services. The findings, based on a survey of 712 responses, provide special empirical insights on the gaps that can arise from inconsistent perceptions of expectations and experiences between the students and the university. Finally, implications for university administration, marketing and research are presented

Multi-Component and Multi-Dimensional Mathematical Modeling of Solid Oxide Fuel Cells

Solid oxide fuel cells (SOFCs) are solid-state ceramic cells, typically operating between 1073 K and 1273 K. Because of high operating temperature, SOFCs are mostly applicable in stationary power generation. Among various configurations in which SOFCs exist, the planar configuration of solid oxide fuel cell (SOFC) has the potential to offer high power density due to shorter current path. Moreover, the planar configuration of SOFC is simple to stack and closely resemble the stacking arrangement of polymer electrolyte membrane (PEM) fuel cells. However, due to high operating temperature, there are problems associated with the development and commercialization of planar SOFCs, such as requirement of high temperature gas seals, internal stresses in cell components, and high material and manufacturing costs. Mathematical modeling is an essential tool for the advancement of SOFC technology. Mathematical models can help in gaining insights on the processes occurring inside the fuel cell, and can also aid in the design and optimization of fuel cells by examining the effect of various operating and design conditions on performance. A multi-component and multi-dimensional mathematical model of SOFCs has been developed in this thesis research. One of the novelties of the present model is its treatment of electrodes. An electrode in the present model is treated as two distinct layers referred to as the backing layer and the reaction zone layer. Reaction zone layers are thin layers in the vicinity of the electrolyte layer where electrochemical reactions occur to produce oxide ions, electrons and water vapor. The other important feature of the present model is its flexibility in fuel choice, which implies not only pure hydrogen but also any reformate composition can be used as a fuel. The modified Stefan-Maxwell equations incorporating Knudsen diffusion are used to model multi-component diffusion in the porous backing and reaction zone layers. The coupled governing equations of species, charge and energy along with the constitutive equations in different layers of the cell are solved for numerical solution using the finite volume method and developed code written in the computer language of C++. In addition, the developed numerical model is validated with various experimental data sets published in the open literature. Moreover, it is verified that the electrode in an SOFC can be treated as two distinct layers referred to as the backing layer and the reaction zone layer. The numerical model not only predicts SOFC performance at different operating and design conditions but also provides insight on the phenomena occurring within the fuel cell. In an anode-supported SOFC, the ohmic overpotential is the single largest contributor to the cell potential loss. Also, the cathode and electrolyte overpotentials are not negligible even though their thicknesses are negligible relative to the anode thickness. Moreover, methane reforming and water-gas shift reactions aid in significantly reducing the anode concentration overpotential in the thick anode of an anode-supported SOFC. A worthwhile comparison of performance between anode-supported and self-supported SOFCs reveals that anode-supported design of SOFCs is the potential design for operating at reduced temperatures. A parametric study has also been carried out to investigate the effect of various key operating and design parameters on the performance of an anode-supported SOFC. Reducing the operating temperature below 1073 K results in a significant drop in the performance of an anode-supported SOFC; hence ionic conductivity of the ion-conducting particles in the reaction zone layers and electrolyte needs to be enhanced to operate anode-supported SOFCs below 1073 K. Further, increasing the anode reaction zone layer beyond certain thickness has no significant effect on the performance of an anode-supported SOFC. Moreover, there is a spatial limitation to the transport of oxide ions in the reaction zone layer, thereby reflecting the influence of reaction zone thickness on cell performance

Photochemical air quality modelling in arid regions

Despite continuous measures to control air pollution, large fractions of the population across the world are still exposed to potentially dangerous pollutant concentration levels. Research continues to increase in the area of air pollution with focus on different pollutants and regions. A particular emphasis is on the understanding of the formation of secondary pollutants as their relationships with primary pollutants are complex. One of the key factors that influences these complex relationships is the regional characteristics, such as temperature, humidity, and solar radiations. Arid regions are of particular concern as the characteristics, especially, extreme temperatures and dust storms, deteriorate air quality significantly. The study area chosen for this research is the Riyadh region in Saudi Arabia. Improving the air quality in this region requires further understanding of the formation of secondary pollutants, particularly ozone (O₃). Generally, Photochemical Air Quality Models (PAQM) are employed to study the formation of secondary pollutants in the atmosphere. This research configured high-resolution Community Multiscale Air Quality (CMAQ) model over the area to study the research objectives. This model could be utilized to study various strategies to mitigate photochemical smog formation in the region. The regional characteristics have significant roles in atmospheric chemical mechanisms, and an effective mitigation plan is important for successful air quality management; hence getting a better understanding of the chemical mechanisms is pivotal. This thesis investigated various chemical mechanisms that are present in PAQM constraining with the observed data resulting in the identification of the most appropriate mechanism for arid regions. The key chemical reactions and corresponding kinetics were also ascertained. The identified chemical mechanism will serve as a benchmark for any future implementation of PAQM in Riyadh as well as similar regions. Conventionally, deterministic PAQMs are applied to evaluate the efficacy of a control strategy to achieve air quality standards. Uncertainties are inherent in any mathematical model, including PAQM, and are specific to regional characteristics. Ignoring model uncertainties might yield a false sense of precision about pollutant response to emission controls. Hence, such uncertainties must be identified and quantified for the selection of control policies. This research identified key factors influencing the O₃ precursor responsiveness and characterized the parametric uncertainties influencing the prediction of O₃ to precursor emissions. Devising an appropriate mitigation plan also requires running PAQM for a number of scenarios, which is computationally challenging. To overcome this computational burden, an efficient Reduced Form Model (RFM) was developed. It characterizes the impact of uncertainties in model input parameters on O₃ response to not only precursor emissions (NOₓ and VOCs) but also to dust emissions. The development of an efficient RFM allowed the use of a probabilistic framework to study the impact of various emission mitigation and dust increase scenarios. This RFM enabled the understanding of the impact of various emission reductions on the formation of O₃. The newly incorporated dust parameter in the RFM revealed that the relationship of dust concentrations with O₃ formation is nonlinear. Initially, O₃ concentration decreased with the increase of dust and later increased. The configured PAQM, the identified atmospheric chemical mechanism, and the developed RFM (incorporating the new dust parameter) would facilitate the responsible authorities in devising appropriate O₃ reduction strategies for the study area and similar regions. The endeavour undertaken in this research to advance the understanding of PAQM in arid conditions opens up several avenues of further research. The developed RFM has a potential to be improved, such as adding more types of uncertainties (structural and meteorological) and further validating with comprehensive observed data. Additionally, the RFM could be integrated with economics and health uncertainty models to study the cost of mitigation plans and health impacts. Moreover, air chambers can be setup to get more insight into chemical kinetics under arid conditions especially the role of heterogeneous reactions of NOₓ with dust particles

A study on prescribing trends in respiratory tract infections in a tertiary care hospital

The drug utilization pattern of respiratory tract infections to assess the rational prescribing pattern at tertiary care teaching hospital, endorsing drugs by mark names may undermine a portion of the objectives of fundamental solution idea. Recommending by nonexclusive name causes the clinic drug store to have a superior stock control. This will likewise assist the drug store with purchasing drugs on contract premise, as the quantity of brands is less, in this manner decreasing the perplexity among drug specialists while apportioning. Bland medications are regularly more temperate than the marked ones. With respect to recommending of FDCs, Potential points of interest of FDC's incorporate lessened reactions, expanded patient consistence, cooperative energy and expanded adequacy and decreased cost, potential impediments incorporate unbendable settled measurements proportion, contrary pharmacokinetics, expanded harmfulness, doctor and drug specialist's obliviousness

Osmotic drug delivery system of valsartan

The objective of this study is to design and evaluate a new EOP called swellable elementary osmotic pump (SEOP) of the freely water soluble drug, amitriptyline hydrochloride (1 g /mL) by adding water swellable polymers in the core. The hydrophilic polymers included in the core retard the highly water soluble drug by producing hydrogel within the core, which may restrict and delay the solvent contact with drug molecules and may increase the diffusional length of the solvent to achieve a constant release rate. Thus, this technology can be exploited to achieve constant drug release at predetermined rate especially for highly water soluble drugs

Identification of New Drug Candidates Against \u3cem\u3eBorrelia burgdorferi\u3c/em\u3e Using High-Throughput Screening

Lyme disease is the most common zoonotic bacterial disease in North America. It is estimated that .300,000 cases per annum are reported in USA alone. A total of 10%–20% of patients who have been treated with antibiotic therapy report the recrudescence of symptoms, such as muscle and joint pain, psychosocial and cognitive difficulties, and generalized fatigue. This condition is referred to as posttreatment Lyme disease syndrome. While there is no evidence for the presence of viable infectious organisms in individuals with posttreatment Lyme disease syndrome, some researchers found surviving Borrelia burgdorferi population in rodents and primates even after antibiotic treatment. Although such observations need more ratification, there is unmet need for developing the therapeutic agents that focus on removing the persisting bacterial form of B. burgdorferi in rodent and nonhuman primates. For this purpose, high-throughput screening was done using BacTiter-Glo assay for four compound libraries to identify candidates that stop the growth of B. burgdorferi in vitro. The four chemical libraries containing 4,366 compounds (80% Food and Drug Administration [FDA] approved) that were screened are Library of Pharmacologically Active Compounds (LOPAC1280), the National Institutes of Health Clinical Collection, the Microsource Spectrum, and the Biomol FDA. We subsequently identified 150 unique compounds, which inhibited .90% of B. burgdorferi growth at a concentration of ,25 µM. These 150 unique compounds comprise many safe antibiotics, chemical compounds, and also small molecules from plant sources. Of the 150 unique compounds, 101 compounds are FDA approved. We selected the top 20 FDA-approved molecules based on safety and potency and studied their minimum inhibitory concentration and minimum bactericidal concentration. The promising safe FDA-approved candidates that show low minimum inhibitory concentration and minimum bactericidal concentration values can be chosen as lead molecules for further advanced studies