Muhammad Yousaf Rana - Academia.edu (original) (raw)

Papers by Muhammad Yousaf Rana

Indonesian Journal of Electrical Engineering and Computer Science

This research aims to improve anomaly detection performance by developing two variants of hybrid ... more This research aims to improve anomaly detection performance by developing two variants of hybrid models combining supervised and unsupervised machine learning techniques. Supervised models cannot detect new or unseen types of anomaly. Hence in variant 1, a supervised model that detects normal samples is followed by an unsupervised learning model to screen anomaly. The unsupervised model is weak in differentiating between noise and fraud. Hence in variant 2, the hybrid model incorporates an unsupervised model that detects anomaly is followed by a supervised model to validate an anomaly. Three different datasets are used for model evaluation. The experiment is begun with 5 supervised models and 3 unsupervised models. After performance evaluation, 2 supervised models with the highest F1-Score and one unsupervised model with the best recall value are selected for hybrid model development. The variant 1 hybrid model recorded the best recall value across all the experiments, indicating th...

ArXiv, 2020

With the advent of advanced technology, IoT introduces a vast number of devices connecting with e... more With the advent of advanced technology, IoT introduces a vast number of devices connecting with each other and collecting a sheer volume of data. Thus, the demands of IoT security is paramount. Cryptography is being used to secure the networks for authentication, confidentiality, data integrity and access control. However, due to the resource constraint nature of IoT devices, the traditional cryptographic protocols may not be suited in all IoT environments. Researchers, as a result, have been proposing various lightweight cryptographic algorithms and protocols. In this paper, we discuss the state of the art lightweight cryptographic protocols for IoT networks and present a comparative analysis of the existing protocols. In doing so, this paper has classified the most current algorithm into two parts, such as symmetric and asymmetric lightweight cryptography. Additionally, we consider several recent developed block cipher and stream cipher algorithms. Furthermore, various research ch...

Lecture Notes of the Institute for Computer Sciences, Social Informatics and Telecommunications Engineering, 2021

Blood, 2014

Background: Acquired hemophilia (AH) is an autoimmune disease caused by an autoantibody to factor... more Background: Acquired hemophilia (AH) is an autoimmune disease caused by an autoantibody to factor VIII (FVIII). Morbidity and mortality are high due to the age of the patients, underlying diseases, the toxic effects of immunosuppression, bleeding and is in part attributable to sequential delays in diagnosis and appropriate treatment. Objective: AH usually presents to clinicians without prior experience of the disease, therefore diagnosis is frequently delayed and bleeds under treated. Therefore improving the awareness among health care professionals to whom AH patients are likely to present is our main objective. Also, we believe that, optimal management of AH requires active participation of non-hematologist physicians, pharmacists and laboratory staff with hematologists. Method: For this objective, in May 2013, we carried out a survey among non-hematologist health care professionals including clinicians, clinical pharmacists and laboratory staff in 10 tertiary medical care Arabian...

Coatings, 2019

The present study offers mathematical calculations of the roll-coating procedure lubricated with ... more The present study offers mathematical calculations of the roll-coating procedure lubricated with an upper-convected Maxwell fluid. An incompressible isothermal viscoelastic fluid was considered, with both the roll and the porous web having uniform velocities. By using the lubrication approximation theory, the desired equations of motion for the fluid applied to the porous web were modelled and analyzed. The suction rate on the web and the injection rate at the roll surface were proportionately anticipated. Results for the velocity profile and pressure gradient were received analytically. Fluid parameters of industrial significance (i.e., detachment point, pressure, sheet/roll separating force, power contribution, and coating thickness) were also calculated numerically. A substantial and monotonic increase was witnessed in these quantities with the increase of flow parameters.

Life Science Journal

ABSTRACT

In this paper, the optimal static and the dynamic anti-windup compensators (AWC) are designed usi... more In this paper, the optimal static and the dynamic anti-windup compensators (AWC) are designed using a new improved particle swarm optimization (PSO) algorithm. The existing optimization techniques for AWC make use of LMI (Linear Matrix Inequality) and various concepts of nonlinear control concepts that require complex mathematics. For this optimization, we have developed and utilized an improved version of PSO. In this new improved PSO algorithm, �first the problem-space is explored with constant non-zero inertia factor until the fitness function saturates to a local or global minima. The solution obtained thus far is then further re�nfied by rerunning the algorithm but with inertia factor set to zero. This slight improvement enables a better search for a solution within the already explored problem-space. The optimized static and dynamic AWC is compared with the existing LMI-based AWC for the performance index.

European Radiology

Clinical History Patient admitted via ER in status epilepticus developed cardio-respiratory arres... more Clinical History Patient admitted via ER in status epilepticus developed cardio-respiratory arrest because of hypoxia, 15 minutes CPR done. History of abnormal movements started a few months ago and seizures for the last two weeks. Family history of abnormal movements in brother who died five years ago undiagnosed. No previous investigations available. Imaging Findings Non enhanced CT Brain showing extensive bilateral calcifications involving the basal ganglia, thalami and subcortical white matter of both cerebral and cerebellar hemispheres in symmetric fashion, compatible with Fahr's disease. Cavum variants, "cavum septum pellucidum" and "cavum vergae" are also seen. Infarct involving the right and left occipital lobes and right cerebellar hemisphere are seen. The area of involvement corresponds to the posterior circulation territory.

One of the most important quality measures is process, which includes access to care and timeline... more One of the most important quality measures is process, which includes access to care and timeliness as key dimensions. Reduction of the time taken to transfer admitted patients to ICU from ED helps enhance process greatly. In addition, early admission to ICU of critical patients, not only helps to solve the problem of ED overcrowding, it was also shown by studies to improve patients' outcome. Aims To measure the median time between the decision to admit a patient from ED, and actual arrival to ICU, at King Saud Medical City, Riyadh, KSA. Methods Median time (in minutes) between decision to admit a patient from ED and arrival to ICU, during April 2014 Results The median time between decision to admit and ICU arrival during April 2014 was 100 minutes, which is below our delay deadline of 240 minutes, however, 13 patients were delayed, out of which 7 delays were justified medically, but 6 cases were delayed due to non-medical reasons. Conclusions Despite having a median time betwee...

Journal of Vascular Surgery: Venous and Lymphatic Disorders, 2015

Retained inferior vena cava (IVC) filters can lead to significant complications. Six patients und... more Retained inferior vena cava (IVC) filters can lead to significant complications. Six patients underwent open surgical removal of complicated IVC filters that could not be removed endovascularly. Struts of the filter perforated the IVC wall in all patients and the adjacent viscera in five. Caval clamping and longitudinal cavotomy with direct closure were used in two patients to remove permanent filters. IVC clamping was not needed in three patients, in whom the filter was first collapsed and then removed through a stab venotomy in the IVC (n = 2) or lumbar vein (n = 1). A broken strut that infected the vertebra was removed outside the IVC in the sixth patient. No early or delayed complications, venous thrombosis, or pulmonary embolism was encountered at a mean follow-up of 1.3 years.

Journal of Clinical Virology, 2015

Crimean Congo hemorrhagic fever (CCHF) has been reported from more than 30 countries in Africa, A... more Crimean Congo hemorrhagic fever (CCHF) has been reported from more than 30 countries in Africa, Asia, Eastern Europe and Middle East. The disease is considered endemic in Pakistan and neighboring countries like Iran and Afghanistan. This study aimed to explore the genetic diversity of CCHF virus (CCHFV) detected in Pakistan and Afghanistan based on analysis of partial S-segment sequences. During 2011, one hundred samples satisfying the CCHF case definition were tested by (ELISA) and RT-PCR for detection of IgM antibodies and viral RNA, respectively. Phylogenetic analysis was carried out on partial S-segment nucleotide sequences using MEGA 5.0. Out of one hundred collected during 2011, 49 (49%) were positive for CCHF either by ELISA/RT-PCR or both. The mean age of the CCHFV positive cases was 30.32 years (range 18-56 years) and overall mortality rate was 20.4%. All CCHF virus isolates from this study clustered with strains previously reported from Pakistan, Iran and Afghanistan within the Asia-1 genogroup. Four distinct sub-clades were found circulating within Asia-1 genogroup. Six CCHFV strains found in Pakistan and Afghanistan grouped into a new sub-clade-D. Data from this study shows that endemic foci of CCHFV span the international border between Pakistan and Afghanistan with genetically diverse variants circulating in this region. Our findings emphasize to establish a laboratory based surveillance program and devise health policy measures to control CCHF infection especially in Baluchistan.

Perspectives in vascular surgery and endovascular therapy, 2012

Hybrid approaches for repair of aneurysms involving the ascending aorta and the aortic arch have ... more Hybrid approaches for repair of aneurysms involving the ascending aorta and the aortic arch have been developed to avoid or reduce duration of cardiopulmonary bypass and circulatory arrest and to decrease operative time, blood loss, hospital stay, morbidity, and mortality. These include ascending aorta-based debranching or cervical extra-anatomical bypasses followed by stent-grafting. In patients with associated descending aortic aneurysms, the elephant trunk technique is used followed by stent-grafting of the descending thoracic aorta. A review of the literature of hybrid aortic arch reconstructions, published over past 7 years, reveals perioperative mortalities from 0% to 13%, stroke from 0% to 10%, and spinal cord injury in 0% to 13%. The outcomes are comparable to contemporary results from total open and total endovascular reconstructions in spite of the fact that the hybrid approach is generally taken in patients with high surgical risk for open repair and with prohibitive anat...

SPE/PAPG Annual Technical Conference, 2010

Production drop caused by down hole scale deposition is becoming a serious problem not only in we... more Production drop caused by down hole scale deposition is becoming a serious problem not only in wells producing with high water cut but also in deep, hot, sour gas wells with very low water cuts(trace to 6%). This paper presents a case study of CaCO3 & CaSO4 scale deposition in a sour well in north of Pakistan that resulted in substantial production drop. HCl (15%) was used to dissolve/wash the scale obstruction in the tubular and clean the perforation of well. Although the treatment was successful in dissolving the scale and restoring the production, yet these production gains were lost rapidly. Scale dissolver treatments followed by scale inhibitions were also implemented but no appreciable results were achieved. A detailed in house study was carried out by POL for scale analysis and its removal techniques. Scale monitoring by produced water analysis, gauge cutter runs, production & WHFP fluctuations, gas analysis and review of seven scale cleaning jobs guided to carry out organic ...

World Journal of Mechanics, 2012

In this paper, He's variational iteration method is successfully employed to solve a nonlinear bo... more In this paper, He's variational iteration method is successfully employed to solve a nonlinear boundary value problem arising in the study of thin film flow of a third grade fluid down an inclined plane. For comparison, the same problem is solved by the Adomian decomposition method. The results show that the difference between the two solutions is negligible. The conclusion is that this technique may be considered an alternative and efficient method for finding approximate solutions of both linear and nonlinear boundary value problems. Furthermore, the variational iteration method has an advantage over the decomposition method in that it solves the nonlinear problems without using the Adomian polynomials.

2011 IEEE 12th International Symposium on Computational Intelligence and Informatics (CINTI), 2011

Over the last few decades, many evolutionary algorithms have emerged. One such algorithm is Parti... more Over the last few decades, many evolutionary algorithms have emerged. One such algorithm is Particle Swarm Optimization which emulates social and cognitive behavior of bird-flocks. In this paper, particle swarm optimization algorithm is presented as a robust and highly useful optimization technique to tune the gains of the PID controllers in the two feedback loops of the classic Ball and

Pakistan Journal of Biological Sciences, 2003

SPE/PAPG Annual Technical Conference, 2010

It has been long recognized that using the conventional production logging tool in combination wi... more It has been long recognized that using the conventional production logging tool in combination with the electrical probes measurement for water holdup can resolve the source identification of water inside the borehole. The source of water for single layer reservoir can be identified easily and can be complex for borehole involving multilayers and multiphase. The current limitations with the conventional production logging tool is that it covers the quantitative measurements inside borehole and to some extent qualitative measurement behind casing e.g. temperature profile. The conditions get complex in the absence of cement behind casing and multiple pay zones behind the production casing and thus mixture profile tends to complicate the identification of phases within borehole. An alternative way to identify the hydraulic isolation between layers is to detect fluid movement directly behind the casing. Using a novel approach of Oxygen activation of water, the axial movements of water c...

Virus Research, 2009

Rotaviruses are among the major causes of gastroenteritis and diarrhea among children in develope... more Rotaviruses are among the major causes of gastroenteritis and diarrhea among children in developed as well as the developing countries. The rapidly evolving strain prevalence and circulation have resulted in the emergence of novel strains over the period worldwide. The introduction of G12 prototype in 1987 from Philippines and subsequently re-emergence among most of the Asian countries along with USA and Europe has provoked new research horizons to address the global distribution of rotavirus serotypes. These newly emerging subtypes and their sustenance among the population have posed tremendous challenge to the development of an effectual vaccine with heterotypic protective efficacy. In Pakistan, no data is available regarding the prevalent rotavirus serotypes; therefore, this is the first study to report the prevalence of G12 strain in Pakistan in hospitalized children with diarrhea addressing a dire need of further large-scale epidemiological surveys to resolve the underlying rotavirus isolates in both the hospitalized and the community neonatal and child population before formulating the vaccine introduction policies in the country's routine immunization program.

Seminars in Vascular Surgery, 2013

Stent migration and dislodgment is a potential complication after endovenous stenting of the left... more Stent migration and dislodgment is a potential complication after endovenous stenting of the left renal vein (LRV) for nutcracker syndrome. Our purpose is to describe the technique for endovenous removal of such a dislodged stent that was used in a 36-year-old woman with nutcracker syndrome initially treated with renal vein transposition. Recurrent renal vein compression and symptoms developed and a 14 Â 20-mm self-expanding stent was placed in the LRV and was noted to be dislodged into the inferior vena cava on the first post-procedure day. Through right internal jugular access, the stent was stabilized by cannulating a cell of the stent using a guide wire and an angled angiographic catheter. A 20Fr sheath was then placed via right femoral vein access into the inferior vena cava. The stent lumen was cannulated from femoral approach and the stent straightened with a stiff wire. An 18-mm angioplasty balloon was then used to capture the stent. The stent was then compressed with two 25-mm loop snares while simultaneously deflating the balloon as it was pulled into the 20Fr sheath and removed. The LRV was restented with an 18 Â 40mm self-expanding stent. Stenting of LRV for nutcracker syndrome can result in stent migration. Endovenous removal of such a dislodged self-expanding stent is feasible. Our technique emphasizes stent stabilization with cell cannulation and capture over a larger diameter balloon.

Journal of Clinical Virology, 2012

New genotypes of human parechoviruses have been readily identified after improvement of diverse d... more New genotypes of human parechoviruses have been readily identified after improvement of diverse diagnostic tools. We hereby report the detection of a new genotype, HPeV 12, from a child presented with diarrhea and paralysis. The genetic variability of human parechoviruses has recently expanded defining 16 genotypes however data available covers only 11 genotypes. The present study was designed to determine the genetic characterization of human parechovirus identified in a child with gastroenteritis and acute flaccid paralysis (AFP). Stool samples are referred to Virology Department, NIH-Pakistan for the routine detection of enteroviruses and polioviruses through cell culture and RT-PCR. Five of isolates showing cytopathic effect on L20B cell line but negative for poliovirus were further explored for human parechovirus using multiple cell lines and RT-PCR. Human Coxsackie A virus type 2, 3, 6 and 20 were found in four samples whereas the fifth sample contained human parechovirus genotype 12. Efficient growth of human parechovirus was found on L20B cells while Vero and LLC-MK2 cells showed no apparent cytopathic effect. This study describes the detection of a new human parechovirus genotype (HPeV-12) in a paralytic child with diarrhea. Human parechoviruses are now considered as potential pathogens that may cause a number of serious clinical complications especially in infants and young children. These findings emphasize to conduct large scale epidemiological surveys in the country to understand their association with clinical diseases especially gastroenteritis, respiratory and neurological disorders.

Indonesian Journal of Electrical Engineering and Computer Science

This research aims to improve anomaly detection performance by developing two variants of hybrid ... more This research aims to improve anomaly detection performance by developing two variants of hybrid models combining supervised and unsupervised machine learning techniques. Supervised models cannot detect new or unseen types of anomaly. Hence in variant 1, a supervised model that detects normal samples is followed by an unsupervised learning model to screen anomaly. The unsupervised model is weak in differentiating between noise and fraud. Hence in variant 2, the hybrid model incorporates an unsupervised model that detects anomaly is followed by a supervised model to validate an anomaly. Three different datasets are used for model evaluation. The experiment is begun with 5 supervised models and 3 unsupervised models. After performance evaluation, 2 supervised models with the highest F1-Score and one unsupervised model with the best recall value are selected for hybrid model development. The variant 1 hybrid model recorded the best recall value across all the experiments, indicating th...

ArXiv, 2020

With the advent of advanced technology, IoT introduces a vast number of devices connecting with e... more With the advent of advanced technology, IoT introduces a vast number of devices connecting with each other and collecting a sheer volume of data. Thus, the demands of IoT security is paramount. Cryptography is being used to secure the networks for authentication, confidentiality, data integrity and access control. However, due to the resource constraint nature of IoT devices, the traditional cryptographic protocols may not be suited in all IoT environments. Researchers, as a result, have been proposing various lightweight cryptographic algorithms and protocols. In this paper, we discuss the state of the art lightweight cryptographic protocols for IoT networks and present a comparative analysis of the existing protocols. In doing so, this paper has classified the most current algorithm into two parts, such as symmetric and asymmetric lightweight cryptography. Additionally, we consider several recent developed block cipher and stream cipher algorithms. Furthermore, various research ch...

Lecture Notes of the Institute for Computer Sciences, Social Informatics and Telecommunications Engineering, 2021

Blood, 2014

Background: Acquired hemophilia (AH) is an autoimmune disease caused by an autoantibody to factor... more Background: Acquired hemophilia (AH) is an autoimmune disease caused by an autoantibody to factor VIII (FVIII). Morbidity and mortality are high due to the age of the patients, underlying diseases, the toxic effects of immunosuppression, bleeding and is in part attributable to sequential delays in diagnosis and appropriate treatment. Objective: AH usually presents to clinicians without prior experience of the disease, therefore diagnosis is frequently delayed and bleeds under treated. Therefore improving the awareness among health care professionals to whom AH patients are likely to present is our main objective. Also, we believe that, optimal management of AH requires active participation of non-hematologist physicians, pharmacists and laboratory staff with hematologists. Method: For this objective, in May 2013, we carried out a survey among non-hematologist health care professionals including clinicians, clinical pharmacists and laboratory staff in 10 tertiary medical care Arabian...

Coatings, 2019

The present study offers mathematical calculations of the roll-coating procedure lubricated with ... more The present study offers mathematical calculations of the roll-coating procedure lubricated with an upper-convected Maxwell fluid. An incompressible isothermal viscoelastic fluid was considered, with both the roll and the porous web having uniform velocities. By using the lubrication approximation theory, the desired equations of motion for the fluid applied to the porous web were modelled and analyzed. The suction rate on the web and the injection rate at the roll surface were proportionately anticipated. Results for the velocity profile and pressure gradient were received analytically. Fluid parameters of industrial significance (i.e., detachment point, pressure, sheet/roll separating force, power contribution, and coating thickness) were also calculated numerically. A substantial and monotonic increase was witnessed in these quantities with the increase of flow parameters.

Life Science Journal

ABSTRACT

In this paper, the optimal static and the dynamic anti-windup compensators (AWC) are designed usi... more In this paper, the optimal static and the dynamic anti-windup compensators (AWC) are designed using a new improved particle swarm optimization (PSO) algorithm. The existing optimization techniques for AWC make use of LMI (Linear Matrix Inequality) and various concepts of nonlinear control concepts that require complex mathematics. For this optimization, we have developed and utilized an improved version of PSO. In this new improved PSO algorithm, �first the problem-space is explored with constant non-zero inertia factor until the fitness function saturates to a local or global minima. The solution obtained thus far is then further re�nfied by rerunning the algorithm but with inertia factor set to zero. This slight improvement enables a better search for a solution within the already explored problem-space. The optimized static and dynamic AWC is compared with the existing LMI-based AWC for the performance index.

European Radiology

Clinical History Patient admitted via ER in status epilepticus developed cardio-respiratory arres... more Clinical History Patient admitted via ER in status epilepticus developed cardio-respiratory arrest because of hypoxia, 15 minutes CPR done. History of abnormal movements started a few months ago and seizures for the last two weeks. Family history of abnormal movements in brother who died five years ago undiagnosed. No previous investigations available. Imaging Findings Non enhanced CT Brain showing extensive bilateral calcifications involving the basal ganglia, thalami and subcortical white matter of both cerebral and cerebellar hemispheres in symmetric fashion, compatible with Fahr's disease. Cavum variants, "cavum septum pellucidum" and "cavum vergae" are also seen. Infarct involving the right and left occipital lobes and right cerebellar hemisphere are seen. The area of involvement corresponds to the posterior circulation territory.

One of the most important quality measures is process, which includes access to care and timeline... more One of the most important quality measures is process, which includes access to care and timeliness as key dimensions. Reduction of the time taken to transfer admitted patients to ICU from ED helps enhance process greatly. In addition, early admission to ICU of critical patients, not only helps to solve the problem of ED overcrowding, it was also shown by studies to improve patients' outcome. Aims To measure the median time between the decision to admit a patient from ED, and actual arrival to ICU, at King Saud Medical City, Riyadh, KSA. Methods Median time (in minutes) between decision to admit a patient from ED and arrival to ICU, during April 2014 Results The median time between decision to admit and ICU arrival during April 2014 was 100 minutes, which is below our delay deadline of 240 minutes, however, 13 patients were delayed, out of which 7 delays were justified medically, but 6 cases were delayed due to non-medical reasons. Conclusions Despite having a median time betwee...

Journal of Vascular Surgery: Venous and Lymphatic Disorders, 2015

Retained inferior vena cava (IVC) filters can lead to significant complications. Six patients und... more Retained inferior vena cava (IVC) filters can lead to significant complications. Six patients underwent open surgical removal of complicated IVC filters that could not be removed endovascularly. Struts of the filter perforated the IVC wall in all patients and the adjacent viscera in five. Caval clamping and longitudinal cavotomy with direct closure were used in two patients to remove permanent filters. IVC clamping was not needed in three patients, in whom the filter was first collapsed and then removed through a stab venotomy in the IVC (n = 2) or lumbar vein (n = 1). A broken strut that infected the vertebra was removed outside the IVC in the sixth patient. No early or delayed complications, venous thrombosis, or pulmonary embolism was encountered at a mean follow-up of 1.3 years.

Journal of Clinical Virology, 2015

Crimean Congo hemorrhagic fever (CCHF) has been reported from more than 30 countries in Africa, A... more Crimean Congo hemorrhagic fever (CCHF) has been reported from more than 30 countries in Africa, Asia, Eastern Europe and Middle East. The disease is considered endemic in Pakistan and neighboring countries like Iran and Afghanistan. This study aimed to explore the genetic diversity of CCHF virus (CCHFV) detected in Pakistan and Afghanistan based on analysis of partial S-segment sequences. During 2011, one hundred samples satisfying the CCHF case definition were tested by (ELISA) and RT-PCR for detection of IgM antibodies and viral RNA, respectively. Phylogenetic analysis was carried out on partial S-segment nucleotide sequences using MEGA 5.0. Out of one hundred collected during 2011, 49 (49%) were positive for CCHF either by ELISA/RT-PCR or both. The mean age of the CCHFV positive cases was 30.32 years (range 18-56 years) and overall mortality rate was 20.4%. All CCHF virus isolates from this study clustered with strains previously reported from Pakistan, Iran and Afghanistan within the Asia-1 genogroup. Four distinct sub-clades were found circulating within Asia-1 genogroup. Six CCHFV strains found in Pakistan and Afghanistan grouped into a new sub-clade-D. Data from this study shows that endemic foci of CCHFV span the international border between Pakistan and Afghanistan with genetically diverse variants circulating in this region. Our findings emphasize to establish a laboratory based surveillance program and devise health policy measures to control CCHF infection especially in Baluchistan.

Perspectives in vascular surgery and endovascular therapy, 2012

Hybrid approaches for repair of aneurysms involving the ascending aorta and the aortic arch have ... more Hybrid approaches for repair of aneurysms involving the ascending aorta and the aortic arch have been developed to avoid or reduce duration of cardiopulmonary bypass and circulatory arrest and to decrease operative time, blood loss, hospital stay, morbidity, and mortality. These include ascending aorta-based debranching or cervical extra-anatomical bypasses followed by stent-grafting. In patients with associated descending aortic aneurysms, the elephant trunk technique is used followed by stent-grafting of the descending thoracic aorta. A review of the literature of hybrid aortic arch reconstructions, published over past 7 years, reveals perioperative mortalities from 0% to 13%, stroke from 0% to 10%, and spinal cord injury in 0% to 13%. The outcomes are comparable to contemporary results from total open and total endovascular reconstructions in spite of the fact that the hybrid approach is generally taken in patients with high surgical risk for open repair and with prohibitive anat...

SPE/PAPG Annual Technical Conference, 2010

Production drop caused by down hole scale deposition is becoming a serious problem not only in we... more Production drop caused by down hole scale deposition is becoming a serious problem not only in wells producing with high water cut but also in deep, hot, sour gas wells with very low water cuts(trace to 6%). This paper presents a case study of CaCO3 & CaSO4 scale deposition in a sour well in north of Pakistan that resulted in substantial production drop. HCl (15%) was used to dissolve/wash the scale obstruction in the tubular and clean the perforation of well. Although the treatment was successful in dissolving the scale and restoring the production, yet these production gains were lost rapidly. Scale dissolver treatments followed by scale inhibitions were also implemented but no appreciable results were achieved. A detailed in house study was carried out by POL for scale analysis and its removal techniques. Scale monitoring by produced water analysis, gauge cutter runs, production & WHFP fluctuations, gas analysis and review of seven scale cleaning jobs guided to carry out organic ...

World Journal of Mechanics, 2012

In this paper, He's variational iteration method is successfully employed to solve a nonlinear bo... more In this paper, He's variational iteration method is successfully employed to solve a nonlinear boundary value problem arising in the study of thin film flow of a third grade fluid down an inclined plane. For comparison, the same problem is solved by the Adomian decomposition method. The results show that the difference between the two solutions is negligible. The conclusion is that this technique may be considered an alternative and efficient method for finding approximate solutions of both linear and nonlinear boundary value problems. Furthermore, the variational iteration method has an advantage over the decomposition method in that it solves the nonlinear problems without using the Adomian polynomials.

2011 IEEE 12th International Symposium on Computational Intelligence and Informatics (CINTI), 2011

Over the last few decades, many evolutionary algorithms have emerged. One such algorithm is Parti... more Over the last few decades, many evolutionary algorithms have emerged. One such algorithm is Particle Swarm Optimization which emulates social and cognitive behavior of bird-flocks. In this paper, particle swarm optimization algorithm is presented as a robust and highly useful optimization technique to tune the gains of the PID controllers in the two feedback loops of the classic Ball and

Pakistan Journal of Biological Sciences, 2003

SPE/PAPG Annual Technical Conference, 2010

It has been long recognized that using the conventional production logging tool in combination wi... more It has been long recognized that using the conventional production logging tool in combination with the electrical probes measurement for water holdup can resolve the source identification of water inside the borehole. The source of water for single layer reservoir can be identified easily and can be complex for borehole involving multilayers and multiphase. The current limitations with the conventional production logging tool is that it covers the quantitative measurements inside borehole and to some extent qualitative measurement behind casing e.g. temperature profile. The conditions get complex in the absence of cement behind casing and multiple pay zones behind the production casing and thus mixture profile tends to complicate the identification of phases within borehole. An alternative way to identify the hydraulic isolation between layers is to detect fluid movement directly behind the casing. Using a novel approach of Oxygen activation of water, the axial movements of water c...

Virus Research, 2009

Rotaviruses are among the major causes of gastroenteritis and diarrhea among children in develope... more Rotaviruses are among the major causes of gastroenteritis and diarrhea among children in developed as well as the developing countries. The rapidly evolving strain prevalence and circulation have resulted in the emergence of novel strains over the period worldwide. The introduction of G12 prototype in 1987 from Philippines and subsequently re-emergence among most of the Asian countries along with USA and Europe has provoked new research horizons to address the global distribution of rotavirus serotypes. These newly emerging subtypes and their sustenance among the population have posed tremendous challenge to the development of an effectual vaccine with heterotypic protective efficacy. In Pakistan, no data is available regarding the prevalent rotavirus serotypes; therefore, this is the first study to report the prevalence of G12 strain in Pakistan in hospitalized children with diarrhea addressing a dire need of further large-scale epidemiological surveys to resolve the underlying rotavirus isolates in both the hospitalized and the community neonatal and child population before formulating the vaccine introduction policies in the country's routine immunization program.

Seminars in Vascular Surgery, 2013

Stent migration and dislodgment is a potential complication after endovenous stenting of the left... more Stent migration and dislodgment is a potential complication after endovenous stenting of the left renal vein (LRV) for nutcracker syndrome. Our purpose is to describe the technique for endovenous removal of such a dislodged stent that was used in a 36-year-old woman with nutcracker syndrome initially treated with renal vein transposition. Recurrent renal vein compression and symptoms developed and a 14 Â 20-mm self-expanding stent was placed in the LRV and was noted to be dislodged into the inferior vena cava on the first post-procedure day. Through right internal jugular access, the stent was stabilized by cannulating a cell of the stent using a guide wire and an angled angiographic catheter. A 20Fr sheath was then placed via right femoral vein access into the inferior vena cava. The stent lumen was cannulated from femoral approach and the stent straightened with a stiff wire. An 18-mm angioplasty balloon was then used to capture the stent. The stent was then compressed with two 25-mm loop snares while simultaneously deflating the balloon as it was pulled into the 20Fr sheath and removed. The LRV was restented with an 18 Â 40mm self-expanding stent. Stenting of LRV for nutcracker syndrome can result in stent migration. Endovenous removal of such a dislodged self-expanding stent is feasible. Our technique emphasizes stent stabilization with cell cannulation and capture over a larger diameter balloon.

Journal of Clinical Virology, 2012

New genotypes of human parechoviruses have been readily identified after improvement of diverse d... more New genotypes of human parechoviruses have been readily identified after improvement of diverse diagnostic tools. We hereby report the detection of a new genotype, HPeV 12, from a child presented with diarrhea and paralysis. The genetic variability of human parechoviruses has recently expanded defining 16 genotypes however data available covers only 11 genotypes. The present study was designed to determine the genetic characterization of human parechovirus identified in a child with gastroenteritis and acute flaccid paralysis (AFP). Stool samples are referred to Virology Department, NIH-Pakistan for the routine detection of enteroviruses and polioviruses through cell culture and RT-PCR. Five of isolates showing cytopathic effect on L20B cell line but negative for poliovirus were further explored for human parechovirus using multiple cell lines and RT-PCR. Human Coxsackie A virus type 2, 3, 6 and 20 were found in four samples whereas the fifth sample contained human parechovirus genotype 12. Efficient growth of human parechovirus was found on L20B cells while Vero and LLC-MK2 cells showed no apparent cytopathic effect. This study describes the detection of a new human parechovirus genotype (HPeV-12) in a paralytic child with diarrhea. Human parechoviruses are now considered as potential pathogens that may cause a number of serious clinical complications especially in infants and young children. These findings emphasize to conduct large scale epidemiological surveys in the country to understand their association with clinical diseases especially gastroenteritis, respiratory and neurological disorders.