Computational Fluid Dynamics (CFD) Simulation and Comparison for Different Numbers of Baffles to Reduce Concentration Polarization Effects in Membrane Tubes

This research shows the use of computational fluid dynamics (CFD) with finite volume method (FVM) to study the species diffusion and mixing characteristics in a tubular membrane filled with vertical baffles. This study exhibits how to set up the FVM for CFD simulation and residence time distribution (RTD) analysis and compare the mixing characteristics of two membrane tubes with a different number of baffles using RTD curves. In this study, the effects of the number of baffles on flow patterns, features and behavior of air were identified completely through computational fluid dynamics (CFD) simulations. In addition, a two-dimensional simulation was implemented to study the effects of steady and unsteady (transient) flow in the tubular membrane. The residence time distribution (RTD) of a tracer in a co-current flow pattern was investigated. For this, the tracer was injected for 1 second into the membrane tubes on a frozen flow field and the concentration variation of the tracer over time was monitored at the outlet

Research fatigue among injecting drug users in Karachi, Pakistan

Background Karachi is the largest metropolis of Pakistan and its economic hub attracting domestic migrants for economic opportunities. It is also the epicenter of HIV epidemic in the country. Since 2004, one pilot study and four behavioral and biological surveillance rounds have been conducted in Karachi. In addition many student research projects have also focused on key risk groups including injection drug users (IDUs). As a result of this extra ordinary exposure of same kind of questions, IDUs know how to respond to high value questions related to sharing of needles or unsafe sexual practices. The purpose of the study was to explore the element of research fatigue among IDUs in Karachi, Pakistan. Methods The study was conducted on 32 spots in Karachi, selected on the basis of estimate of IDUs at each spot. A trained field worker (recovered IDU) visited each spot; observed sharing behavior of IDUs and asked questions related to practices in January 2009. Verbal consent was obtained from each respondent before asking questions. Results On average 14 IDUs were present at each spot and out of 32 selected spots, 81% were active while more than two groups were present at 69% spots. In each group three to four IDUs were present and everyone in the group was sharing. One dose of injecting narcotics was observed. Sharing of syringes, needles and distilled water was observed at 63% spots while professional injector/street doctor was present at 60% spots. Conclusion There is a need to check internal consistency in surveillance research. It is highly likely that IDUs and other risk groups know how to respond to key questions but their responses do not match with the practices

Knowledge and attitude pertinent to COVID-19 and willingness to COVID vaccination among medical students of University College of Medicine & Dentistry Lahore

Objectives: To determine the awareness and beliefs of medical students towards Corona disease and the COVID-19 vaccine and to assess the willingness to get vaccinated against COVID-19. Methods: This was a cross sectional study conducted on undergraduate medical students at University College of Medicine and dentistry, University of Lahore (UOL). A self-developed questionnaire containing demographic information, 8 knowledge and attitude items and 11 items for perceptions and willingness to get COVID-19 vaccine was completed by 410 participants.  Results: More than ninety five percent of participants were aware of the cause, mode of transmission and mortality associated with corona disease; however, a handful of them knew about the purpose of using vaccine. Majority of the participants believed that COVID-19 vaccine will be effective and a good way to get protected from the disease. Regarding willingness to get cocid-19 vaccine, more than half of the participants wanted to be the first to get vaccinated but majority were concerned about the safety of COVID-19 vaccine.  Conclusion: The medical students of University College of Medicine and dentistry, University of Lahore (UOL) displayed an adequate level of knowledge and awareness towards COVID-19 and a positive attitude about COVID-19 vaccine. Our study noted a high level of COVID-19 vaccine acceptance among medical students, yet there were significant concerns about the safety of vaccine

An Unsupervised Approach for Sentiment Analysis on Social Media Short Text Classification in Roman Urdu

During the last two decades, sentiment analysis, also known as opinion mining, has become one of the most explored research areas in Natural Language Processing (NIP) and data mining. Sentiment analysis focuses on the sentiments or opinions of consumers expressed over social media or different web sites. Due to exposure on the Internet, sentiment analysis has attracted vast numbers of researchers over the globe. A large amount of research has been conducted in English, Chinese, and other languages used worldwide. However, Roman Urdu has been neglected despite being the third most used language for communication in the world, covering millions of users around the globe. Although some techniques have been proposed for sentiment analysis in Roman Urdu, these techniques are limited to a specific domain or developed incorrectly due to the unavailability of language resources available for Roman Urdu. Therefore, in this article, we are proposing an unsupervised approach for sentiment analysis in Roman Urdu. First, the proposed model normalizes the text to overcome spelling variations of different words. After normalizing text, we have used Roman Urdu and English opinion lexicons to correctly identify users\u27 opinions from the text. We have also incorporated negation terms and stemming to assign polarities to each extracted opinion. Furthermore, our model assigns a score to each sentence on the basis of the polarities of extracted opinions and classifies each sentence as positive, negative, or neutral. In order to verify our approach, we have conducted experiments on two publicly available datasets for Roman Urdu and compared our approach with the existing model. Results have demonstrated that our approach outperforms existing models for sentiment analysis tasks in Roman Urdu. Furthermore, our approach does not suffer from domain dependency

Effect of carbofuran on the diversity and mean abundance of ground spiders

The effect of carbofuran on the diversity, richness, evenness and abundance of ground spiders is documented in the present study. Two fields (control and treated) were selected in district Kasur during 2008 and 2009. Pitfall traps were used to collect ground spiders. A total of 1629 specimens of spiders, belonging to 8 families, 16 genera and 24 species were recoded from control field while 1173 specimens belonging to 8 families, 14 genera and 20 species were recorded from the treated field. The most dominant family and species in both the fields were Lycosidae and Lycosa terrestris, respectively. Family Lycosidae accounted more than 90% of the total spider sample. Diversity, richness and evenness of ground spiders in the treated and untreated field did not differ. However, the abundance of dominat spiders declined significantly in the carbofuran treated field. It is concluded that the use of carbofuran is a serious threat to the ground spiders, the important group of biological control agents. So, the use of carbofuran should be minimized in the fields.Key words: Ground spiders, carbofuran, natural predators, pest reduction

Optimization Of Hydrocarbon Ejector Using Computational Fluid Dynamics

Ejector is a powerful emerging thermo-compressor, which is more effective when used with hydrocarbon refrigerants because of its unique thermophysical properties. Therefore, in the present work, a steam ejector model is designed and validated with experimental results to evaluate its accuracy, followed by a detailed comparative study of hydrocarbons and synthetic refrigerants namely pentane, propane, butane, iso-butane, R1234-ze and R1234-yf by computational fluid dynamics and literature Review. The effectiveness of both classes of refrigerants is measured through entrainment ratio, critical backpressure, and thermophysical properties (Literature Review). Pentane was selected as a working fluid since it has comparatively high combination of entrainment ratio and critical back pressure with refrigeration compatible properties. Lastly, the optimized geometry was simulated by varying diameter of constant area zone, nozzle exit position and nozzle expansion angle through Computational Fluid dynamics. The simulation results provide insight into shockwaves, boundary layer separation, vortex formation of ejector flow

Diagnostic issues and clinical spectrum of childhood degenerative brain diseases

To find out the spectrum of clinical presentation and typesof neurodegenerative disorders of childhoodin tertiary care child neurology centre of Pakistan. To find out the role of brain imaging in the diagnosis of degenerative brain disorders in children. Methods: It will bea retrospective, descriptive study conducted at department of paediatric neurology,The Children’s Hospital, Institute of child health, Lahore, Pakistanfrom January 1st,2004 to December 31,2013 (10 years). A total of 22,737 patients were admitted in the Paediatric Neurology department in the above said period. Out of them 366 children fulfilled the inclusion criteria. History, clinical examination and relevant investigations were evaluated from the files manually and proformas were filled. Results: Male to female ratio was 1.43:1 with 78% incidence of consanguinity. Age range was twenty five months to eighteen years. Metachromatic leukodystrophy was the predominant type(21%) followed by adrenoleukodystrophy(1%) and cerebral atrophy (9.5%)and 3% of each Alexander disease, Hellervordenspatz disease, one case each of multiple sclerosis and ataxia telangiectasia. Conclusion: Degenerative brain diseases are common entity in paediatric population. Commonest presentation is regression of mile stones with variable presentation. General pediatriciansmust be aware of their clinical presentation look into it when dealing with children having regression of milestones to diagnosethem earlier.Because of limited diagnostic modalities, brain imaging has significant valve. Facilities for molecular genetics and enzymes should have been available. Regional diagnostics laboratories should have been established and more research is required in this area

Distributed Analysis and Load Balancing System for Grid Enabled Analysis on Hand-held devices using Multi-Agents Systems

Handheld devices, while growing rapidly, are inherently constrained and lack the capability of executing resource hungry applications. This paper presents the design and implementation of distributed analysis and load-balancing system for hand-held devices using multi-agents system. This system enables low resource mobile handheld devices to act as potential clients for Grid enabled applications and analysis environments. We propose a system, in which mobile agents will transport, schedule, execute and return results for heavy computational jobs submitted by handheld devices. Moreover, in this way, our system provides high throughput computing environment for hand-held devices.Comment: 4 pages, 3 figures. Proceedings of the 3rd International Conference on Grid and Cooperative Computing (GCC 2004

Formulation Optimization and In-vitro Evaluation of Oral Floating Captopril Matrix Tablets using Factorial Design

Purpose: To develop a zero-order sustained release floating formulation of captopril, and optimize its drug release for enhanced oral bioavailability.Methods: A relatively new approach, 32 full factorial design, was used to formulate floating captopril matrix tablets and to systematically optimize its drug release using varying levels of xanthan gum and hydroxypropyl methylcellulose (HPMC) K100M polymers. Calcium carbonate was used as gasgenerating agent. After setting the levels by preliminary trials, nine tablet formulations (F1 - F9) were prepared by wet granulation method using Design Expert Software® - suggested combinations of polymers. The concentrations of HPMC K100M (X1) and xanthan gum (X2) were chosen as control variables. Conversely, the response variables selected were timed to release 50 % of the drug (t50%) at 6 h (Q6) and 12 h (Q12). Fourier transform infrared (FTIR) spectroscopy and differential scanning calorimetry (DSC) were used to assess compatibility between the drug and the excipients. The validity of the developed mathematical equations was assessed by designing three extra check-points.Results: The response surface plots drawn demonstrated the suitability of the hydrophilic matrixforming agents for formulating controlled release floating tablets of captopril. FTIR and DSC spectra showed no noticeable incompatibility between drug and polymers in both physical mixtures and in formulations. Floating time lag remained < 5.5 min with floating duration > 12 h. Considerable agreement was observed between predicted and actual release parameters. Fitting the data into different kinetic models showed that non-Fickian behavior for diffusion exponent (n) differed from 0.588 and 0.811.Conclusion: Optimum formulation (F4) showed satisfactory release profile. Moreover, the study successfully demonstrated influence of polymer blends in controlling release variables.Keywords: Captopril, Xanthan gum, Hydroxy propyl methyl cellulose , Factorial design, Bioavailabilit