Saad Khan - Academia.edu (original) (raw)

Papers by Saad Khan

Research paper thumbnail of OCEAN: A Non-Conventional Parameter Free Clustering Algorithm Using Relative Densities of Categories

International Journal of Pattern Recognition and Artificial Intelligence, 2020

In this paper, we propose a fully autonomous density-based clustering algorithm named ‘Ocean’, wh... more In this paper, we propose a fully autonomous density-based clustering algorithm named ‘Ocean’, which is inspired by the oceanic landscape and phenomena that occur in it. Ocean is an improvement over conventional algorithms regarding both distance metric and the clustering mechanism. Ocean defines the distance between two categories as the difference in the relative densities of categories. Unlike existing approaches, Ocean neither assigns the same distance to all pairs of categories, nor assigns arbitrary weights to matches and mismatches between categories that can lead to clustering errors. Ocean uses density ratios of adjacent regions in multidimensional space to detect the edges of the clusters. Ocean is robust against clusters of identical patterns. Unlike conventional approaches, Ocean neither makes any assumption regarding the data distribution within clusters, nor requires tuning of free parameters. Empirical evaluations demonstrate improved performance of Ocean over existin...

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Polymer of intrinsic microporosity (PIM) based fibrous mat: combining particle filtration and rapid catalytic hydrolysis of chemical warfare agent simulants into a highly sorptive, breathable, and mechanically robust fiber matrix

Materials Today Advances, 2020

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Cellulose Silica Hybrid Nanofiber Aerogels: From Sol–Gel Electrospun Nanofibers to Multifunctional Aerogels

Advanced Functional Materials, 2019

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Head and neck neuroendocrine tumors at a single institution over 15 years

Clinical Case Reports, 2019

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Anesthetic considerations for a patient with myasthenia gravis undergoing deep sedation in an outpatient oral surgery setting

Journal of Dental Anesthesia and Pain Medicine, 2019

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Activity and pharmacology of homemade silver nanoparticles in refractory metastatic head and neck squamous cell cancer

Head & Neck, 2018

Silver nanoparticles (AgNP) show efficacy in cancer cell lines. We present the first in-human out... more Silver nanoparticles (AgNP) show efficacy in cancer cell lines. We present the first in-human outcome of AgNP in a cancer patient. Homemade AgNP solution is manufactured using online instructions by a 78-year old male. He started consuming AgNP while on hospice after he developed nasal cavity squamous cell cancer metastatic to liver and lung. Electron microscopy of AgNP solution revealed bimodal nanoparticle size distribution: 3 and 12 nm. Inductively coupled plasma mass spectrometry showed basal silver ion concentrations of 32 ng/g, rising to 46 ng/g 1 hour after ingesting 60 mL of AgNP solution. Urine showed no AgNP. No toxicities were observed and he had complete radiographic resolution of his cancer. He remains without evidence of cancer 18 months later. AgNP ingestion was associated with sustained radiographic resolution of cancer. Further testing of AgNP should be done to confirm its efficacy in head and neck cancer.

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Value of routine preoperative tests for coagulation before elective cranial surgery. Results of an institutional audit and a nationwide survey of neurosurgical centers in Pakistan

World neurosurgery, Jan 3, 2018

Routine preoperative blood testing has become a dogma. The general practice is to order preoperat... more Routine preoperative blood testing has become a dogma. The general practice is to order preoperative work up as a knee jerk response rather than individualize it for each patient. The fact that the bleeding brain tends to swell, which coupled with limited options for proximal control, packing and overall hemostasis, leads to an over emphasis on preoperative coagulation profile. This is a retrospective review of the medical records of patients admitted at Aga Khan University Hospital from January 2010 to December 2015 for an elective craniotomy. The hospital registry was used to identify files for review. Data was collected on a predefined proforma. A nationwide survey was performed and 30 neurosurgery centers were contacted across Pakistan to confirm the practice of preoperative workup. The survey revealed that all centers had a similar practice of preoperative workup. This included CBC, serum electrolytes and coagulation profile; including PT, aPTT and INR. A total of 1800 files we...

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Factors associated with faculty participation in research activities in dental schools

Singapore dental journal, Dec 1, 2017

To quantify participation in dental research activities in Malaysia, and investigate its associat... more To quantify participation in dental research activities in Malaysia, and investigate its association with socio-demographic and professional characteristics, and perceptions of research and development (R&D) culture. Dental academics in Malaysian dental schools were invited to complete a questionnaire by email and post. The survey comprised questions on research activities in the past 12 months, socio-demographic and professional characteristics, and the R&D Culture Index. Principal components factor analysis was carried out to confirm the factor structure of the R&D Culture Index. Chi-square test was used to identify association of research activities with R&D culture, and socio-demographic and professional characteristics. Binary logistic regression was carried to identify predicators of research activities. Of 256 potential participants contacted, 128 (50%) useable responses were returned. Three R&D Culture factors accounting for 57.4% of variance were extracted. More positive pe...

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Prediction of the effects of friction control on top-of-rail cracks

Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit, 2016

Rolling contact fatigue is a major problem connected with railway tracks, especially in curves, s... more Rolling contact fatigue is a major problem connected with railway tracks, especially in curves, since it leads to higher maintenance costs. By optimising the top-of-rail friction, the wear and cracks on the top of the rail can eventually be reduced without causing very long braking distances. There are several research articles available on crack prediction, but most of the research is focused either on rail without a friction modifier or on wheels with and without friction control. In the present study, in order to predict the formation of surface-initiated rolling contact fatigue, a range of friction coefficients with different Kalker’s reduction factors has been assumed. Kalker’s reduction factor takes care of the basic tendency of creepage as a function of the traction forces at lower creepage. The assumed range covers possible friction values from those for non-lubricated rail to those for rail with a minimum measured friction control on the top of the rail using a friction mod...

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Cerebellopontine angle primitive neuroectodermal tumor mimicking trigeminal schwannoma

Surgical Neurology International, 2016

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Electrospun Ultrafine Fiber Composites Containing Fumed Silica: From Solution Rheology to Materials with Tunable Wetting

Langmuir : the ACS journal of surfaces and colloids, Jan 19, 2015

Fumed silica (FS) particles with hydrophobic (R805) or hydrophilic (A150) surface functionalities... more Fumed silica (FS) particles with hydrophobic (R805) or hydrophilic (A150) surface functionalities are incorporated in polyacrylonitrile (PAN) fibers by electrospinning to produce mats with controlled wettability. Rheological measurements are conducted to elucidate the particle-polymer interactions and characterize the system while microscopic and analytic tools are used to examine FS location within both fibers and films to aid in fundamental understanding of the wetting behavior. Unlike traditional polymers, we find these systems to be gel-like, yet electrospinnable; the fumed silica networks breaking down into smaller aggregates during the electrospinning process and dispersing both within and on the surface of the fibers. Composite nanofiber mats containing R805 FS exhibit an apparent contact angle over 130o and remain hydrophobic over 30 minutes, while similar mats with A150 display surface-wetting with a static contact angle of ~30o. Wicking experiments reveal that the water ab...

Bookmarks Related papers MentionsView impact

Research paper thumbnail of A phase 1 safety study of veliparib combined with cisplatin and etoposide in extensive stage small cell lung cancer: A trial of the ECOG–ACRIN Cancer Research Group (E2511)

Lung Cancer, 2015

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Galactomannan binding agents for silicon anodes in Li-ion batteries

J. Mater. Chem. A, 2015

The high Li-extraction capacity can be owed to the favorable interactions between silicon nanopar... more The high Li-extraction capacity can be owed to the favorable interactions between silicon nanoparticles and the galactomannan binders.

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Effects of Composition and Matrix Polarity on Network Development in Organogels of Poly(ethylene glycol) and Dibenzylidene Sorbitol

Langmuir, 2003

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Pakistan and the Organization of Islamic Conference

Westphalian notions of territorial nationhood. The founding fathers of this State had a vision th... more Westphalian notions of territorial nationhood. The founding fathers of this State had a vision that the Muslims of subcontinent should have a separate homeland where they would be able to lead their lives in accordance with the tenets of Islam. Outnumbered three to one in a united India, they propounded the two-nation theory and sought and got a new State on the basis of religion. At the time of its inception and till roughly quarter of a century thereafter, it remained the largest Muslim State on the planet population-wise, and fifth largest in the world. It was natural for it to look towards other Muslim States for camaraderie and support. Thence began Pakistan's Odyssey in quest of pan-Islamism.

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Tracer Microrheology Study of a Hydrophobically-modified Comblike Associative Polymer

Langmuir, 2015

The viscoelastic properties of associative polymers are important not only for their use as rheol... more The viscoelastic properties of associative polymers are important not only for their use as rheology modifiers but also to understand their complex structure in aqueous media. In this study, the dynamics of comblike hydrophobically modified alkali swellable associative (HASE) polymers are probed using diffusing wave spectroscopy (DWS) based tracer microrheology. DWS-based tracer microrheology accurately probes the dynamics of HASE polymers, and the extracted microrheological moduli versus frequency profile obtained from this technique closely matches that obtained from rotational rheometry measurements. Quantitatively, however, the moduli extracted from DWS-based tracer microrheology measurements are slightly higher than those obtained using rotational rheometry. The creep compliance, elastic modulus, and relaxation time concentration scaling behavior exhibits a power-law dependence. The length scale associated with the elastic to glassy behavior change is obtained from the time-dependent diffusion coefficient. The Zimm-Rouse type scaling is recovered at high frequencies but shows a concentration effect switching from Zimm to more Rouse-like behavior at higher concentrations.

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Some of the ethnobotanically important plants of Godi Khel and its outskirts hilly areas, District Karak, Pakistan

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Enzymatic Modification of Guar Solutions

Water Soluble Polymers, 2002

Structurally modified guar galactomannans find application in food and petroleum industries as rh... more Structurally modified guar galactomannans find application in food and petroleum industries as rheology modifiers. Enzymes provide a powerful and convenient method to modify guar structure. In this study, the kinetics of enzymatic degradation of guar solutions were ...

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Bridge protection algorithms – A technique for fault-tolerance in sensor networks

Ad Hoc Networks, 2015

Bookmarks Related papers MentionsView impact

Research paper thumbnail of A History of Saudi Arabia

Foreign Affairs, 2003

Bookmarks Related papers MentionsView impact

Research paper thumbnail of OCEAN: A Non-Conventional Parameter Free Clustering Algorithm Using Relative Densities of Categories

International Journal of Pattern Recognition and Artificial Intelligence, 2020

In this paper, we propose a fully autonomous density-based clustering algorithm named ‘Ocean’, wh... more In this paper, we propose a fully autonomous density-based clustering algorithm named ‘Ocean’, which is inspired by the oceanic landscape and phenomena that occur in it. Ocean is an improvement over conventional algorithms regarding both distance metric and the clustering mechanism. Ocean defines the distance between two categories as the difference in the relative densities of categories. Unlike existing approaches, Ocean neither assigns the same distance to all pairs of categories, nor assigns arbitrary weights to matches and mismatches between categories that can lead to clustering errors. Ocean uses density ratios of adjacent regions in multidimensional space to detect the edges of the clusters. Ocean is robust against clusters of identical patterns. Unlike conventional approaches, Ocean neither makes any assumption regarding the data distribution within clusters, nor requires tuning of free parameters. Empirical evaluations demonstrate improved performance of Ocean over existin...

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Polymer of intrinsic microporosity (PIM) based fibrous mat: combining particle filtration and rapid catalytic hydrolysis of chemical warfare agent simulants into a highly sorptive, breathable, and mechanically robust fiber matrix

Materials Today Advances, 2020

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Cellulose Silica Hybrid Nanofiber Aerogels: From Sol–Gel Electrospun Nanofibers to Multifunctional Aerogels

Advanced Functional Materials, 2019

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Head and neck neuroendocrine tumors at a single institution over 15 years

Clinical Case Reports, 2019

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Anesthetic considerations for a patient with myasthenia gravis undergoing deep sedation in an outpatient oral surgery setting

Journal of Dental Anesthesia and Pain Medicine, 2019

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Activity and pharmacology of homemade silver nanoparticles in refractory metastatic head and neck squamous cell cancer

Head & Neck, 2018

Silver nanoparticles (AgNP) show efficacy in cancer cell lines. We present the first in-human out... more Silver nanoparticles (AgNP) show efficacy in cancer cell lines. We present the first in-human outcome of AgNP in a cancer patient. Homemade AgNP solution is manufactured using online instructions by a 78-year old male. He started consuming AgNP while on hospice after he developed nasal cavity squamous cell cancer metastatic to liver and lung. Electron microscopy of AgNP solution revealed bimodal nanoparticle size distribution: 3 and 12 nm. Inductively coupled plasma mass spectrometry showed basal silver ion concentrations of 32 ng/g, rising to 46 ng/g 1 hour after ingesting 60 mL of AgNP solution. Urine showed no AgNP. No toxicities were observed and he had complete radiographic resolution of his cancer. He remains without evidence of cancer 18 months later. AgNP ingestion was associated with sustained radiographic resolution of cancer. Further testing of AgNP should be done to confirm its efficacy in head and neck cancer.

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Value of routine preoperative tests for coagulation before elective cranial surgery. Results of an institutional audit and a nationwide survey of neurosurgical centers in Pakistan

World neurosurgery, Jan 3, 2018

Routine preoperative blood testing has become a dogma. The general practice is to order preoperat... more Routine preoperative blood testing has become a dogma. The general practice is to order preoperative work up as a knee jerk response rather than individualize it for each patient. The fact that the bleeding brain tends to swell, which coupled with limited options for proximal control, packing and overall hemostasis, leads to an over emphasis on preoperative coagulation profile. This is a retrospective review of the medical records of patients admitted at Aga Khan University Hospital from January 2010 to December 2015 for an elective craniotomy. The hospital registry was used to identify files for review. Data was collected on a predefined proforma. A nationwide survey was performed and 30 neurosurgery centers were contacted across Pakistan to confirm the practice of preoperative workup. The survey revealed that all centers had a similar practice of preoperative workup. This included CBC, serum electrolytes and coagulation profile; including PT, aPTT and INR. A total of 1800 files we...

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Factors associated with faculty participation in research activities in dental schools

Singapore dental journal, Dec 1, 2017

To quantify participation in dental research activities in Malaysia, and investigate its associat... more To quantify participation in dental research activities in Malaysia, and investigate its association with socio-demographic and professional characteristics, and perceptions of research and development (R&D) culture. Dental academics in Malaysian dental schools were invited to complete a questionnaire by email and post. The survey comprised questions on research activities in the past 12 months, socio-demographic and professional characteristics, and the R&D Culture Index. Principal components factor analysis was carried out to confirm the factor structure of the R&D Culture Index. Chi-square test was used to identify association of research activities with R&D culture, and socio-demographic and professional characteristics. Binary logistic regression was carried to identify predicators of research activities. Of 256 potential participants contacted, 128 (50%) useable responses were returned. Three R&D Culture factors accounting for 57.4% of variance were extracted. More positive pe...

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Prediction of the effects of friction control on top-of-rail cracks

Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit, 2016

Rolling contact fatigue is a major problem connected with railway tracks, especially in curves, s... more Rolling contact fatigue is a major problem connected with railway tracks, especially in curves, since it leads to higher maintenance costs. By optimising the top-of-rail friction, the wear and cracks on the top of the rail can eventually be reduced without causing very long braking distances. There are several research articles available on crack prediction, but most of the research is focused either on rail without a friction modifier or on wheels with and without friction control. In the present study, in order to predict the formation of surface-initiated rolling contact fatigue, a range of friction coefficients with different Kalker’s reduction factors has been assumed. Kalker’s reduction factor takes care of the basic tendency of creepage as a function of the traction forces at lower creepage. The assumed range covers possible friction values from those for non-lubricated rail to those for rail with a minimum measured friction control on the top of the rail using a friction mod...

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Cerebellopontine angle primitive neuroectodermal tumor mimicking trigeminal schwannoma

Surgical Neurology International, 2016

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Electrospun Ultrafine Fiber Composites Containing Fumed Silica: From Solution Rheology to Materials with Tunable Wetting

Langmuir : the ACS journal of surfaces and colloids, Jan 19, 2015

Fumed silica (FS) particles with hydrophobic (R805) or hydrophilic (A150) surface functionalities... more Fumed silica (FS) particles with hydrophobic (R805) or hydrophilic (A150) surface functionalities are incorporated in polyacrylonitrile (PAN) fibers by electrospinning to produce mats with controlled wettability. Rheological measurements are conducted to elucidate the particle-polymer interactions and characterize the system while microscopic and analytic tools are used to examine FS location within both fibers and films to aid in fundamental understanding of the wetting behavior. Unlike traditional polymers, we find these systems to be gel-like, yet electrospinnable; the fumed silica networks breaking down into smaller aggregates during the electrospinning process and dispersing both within and on the surface of the fibers. Composite nanofiber mats containing R805 FS exhibit an apparent contact angle over 130o and remain hydrophobic over 30 minutes, while similar mats with A150 display surface-wetting with a static contact angle of ~30o. Wicking experiments reveal that the water ab...

Bookmarks Related papers MentionsView impact

Research paper thumbnail of A phase 1 safety study of veliparib combined with cisplatin and etoposide in extensive stage small cell lung cancer: A trial of the ECOG–ACRIN Cancer Research Group (E2511)

Lung Cancer, 2015

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Galactomannan binding agents for silicon anodes in Li-ion batteries

J. Mater. Chem. A, 2015

The high Li-extraction capacity can be owed to the favorable interactions between silicon nanopar... more The high Li-extraction capacity can be owed to the favorable interactions between silicon nanoparticles and the galactomannan binders.

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Effects of Composition and Matrix Polarity on Network Development in Organogels of Poly(ethylene glycol) and Dibenzylidene Sorbitol

Langmuir, 2003

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Pakistan and the Organization of Islamic Conference

Westphalian notions of territorial nationhood. The founding fathers of this State had a vision th... more Westphalian notions of territorial nationhood. The founding fathers of this State had a vision that the Muslims of subcontinent should have a separate homeland where they would be able to lead their lives in accordance with the tenets of Islam. Outnumbered three to one in a united India, they propounded the two-nation theory and sought and got a new State on the basis of religion. At the time of its inception and till roughly quarter of a century thereafter, it remained the largest Muslim State on the planet population-wise, and fifth largest in the world. It was natural for it to look towards other Muslim States for camaraderie and support. Thence began Pakistan's Odyssey in quest of pan-Islamism.

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Tracer Microrheology Study of a Hydrophobically-modified Comblike Associative Polymer

Langmuir, 2015

The viscoelastic properties of associative polymers are important not only for their use as rheol... more The viscoelastic properties of associative polymers are important not only for their use as rheology modifiers but also to understand their complex structure in aqueous media. In this study, the dynamics of comblike hydrophobically modified alkali swellable associative (HASE) polymers are probed using diffusing wave spectroscopy (DWS) based tracer microrheology. DWS-based tracer microrheology accurately probes the dynamics of HASE polymers, and the extracted microrheological moduli versus frequency profile obtained from this technique closely matches that obtained from rotational rheometry measurements. Quantitatively, however, the moduli extracted from DWS-based tracer microrheology measurements are slightly higher than those obtained using rotational rheometry. The creep compliance, elastic modulus, and relaxation time concentration scaling behavior exhibits a power-law dependence. The length scale associated with the elastic to glassy behavior change is obtained from the time-dependent diffusion coefficient. The Zimm-Rouse type scaling is recovered at high frequencies but shows a concentration effect switching from Zimm to more Rouse-like behavior at higher concentrations.

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Some of the ethnobotanically important plants of Godi Khel and its outskirts hilly areas, District Karak, Pakistan

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Enzymatic Modification of Guar Solutions

Water Soluble Polymers, 2002

Structurally modified guar galactomannans find application in food and petroleum industries as rh... more Structurally modified guar galactomannans find application in food and petroleum industries as rheology modifiers. Enzymes provide a powerful and convenient method to modify guar structure. In this study, the kinetics of enzymatic degradation of guar solutions were ...

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Bridge protection algorithms – A technique for fault-tolerance in sensor networks

Ad Hoc Networks, 2015

Bookmarks Related papers MentionsView impact

Research paper thumbnail of A History of Saudi Arabia

Foreign Affairs, 2003

Bookmarks Related papers MentionsView impact