Mohammad Hussain - Academia.edu (original) (raw)

Papers by Mohammad Hussain

International Journal of Nanomanufacturing, 2010

This paper describes the application of electroforming in the synthesis of nanocrystalline nickel... more This paper describes the application of electroforming in the synthesis of nanocrystalline nickel by very high speed movement of the electrolyte; the principles and mechanisms of electroforming in the production of nanocrystalline structured metallic objects in combination with high speed movement of electrolyte are also described. Nanocrystalline nickel components were formed at a speed exceeding 600 µm per hour; the grain size of the electrodeposited nickel was considerably reduced by high speed movement of the plating solution. When requirements specify high-tolerances, complexity, lightweight and miniature geometry, electroforming is a serious contender and in certain cases may be the only economically viable manufacturing process. AFM characterisation showed that the crystalline/particle sizes of the electroformed objects were less than 30 nm. The nickel deposits were characterised further using SEM/EDAX. The focus of this study is primarily in the application of nanomaterials in industrial gas turbines.

International Journal of Nanoparticles, 2009

ABSTRACT

Micron, 2004

The platelet membrane receptor a IIb b 3 binds to adsorbed protein ligands including fibrinogen, ... more The platelet membrane receptor a IIb b 3 binds to adsorbed protein ligands including fibrinogen, von Willebrand factor and fibronectin, and is critically important in mediating platelet adhesion to damaged subendothelium and to synthetic biomaterial surfaces. This receptor is a member of the integrin family, a highly prevalent class of heterodimeric molecules consisting of a single a and b subunit. In an ongoing effort to understand the mechanisms underlying platelet adhesion events, high-resolution atomic force microscopy (AFM) under dynamic conditions was used to obtain images of a IIb b 3 molecules as well as aggregates of the protein. Images of integrin molecules were obtained by tapping mode AFM under aqueous buffer conditions following adsorption on a series of ultrasmooth model surfaces. On a model hydrophobic surface, detergents stabilizing the protein in solution competed for surface adsorption sites. When this detergent was removed from the system, the protein was predominantly seen as aggregates with head groups pointing outward. A limited number of individual integrin molecules were observed, and were found to have dimensions consistent with those reported previously by electron microscopy studies. Integrin molecules showed weak adhesion to the two hydrophilic surfaces used in the study, although formation of a lipid bilayer around surface-adsorbed molecules improved the resolution. At longer time periods, the integrin molecules embedded in this lipid bilayer exhibited sufficient mobility to form molecular aggregates. The structural measurements described in this study not only reveal threedimensional features of the molecule, they represent an important step towards dynamic adsorption experiments and visualizing the integrin interacting with surface-adsorbed proteins as in biomaterial-induced thrombogenesis.

Journal of Materials Engineering and Performance, 2012

An innovative process has been developed for electroplating of nickel on titanium surface using f... more An innovative process has been developed for electroplating of nickel on titanium surface using fast solution flow technique. Nickel was directly deposited on a titanium alloy without using any pretreatment process. Level of adhesion was determined using quantitative peel test and characterization of the deposition was performed by scanning electron microscopy. Results showed that the rate of nickel deposition at 60 C was higher than that of the rate of nickel deposition at 40 C. Moreover, Watts solution provided higher rate of nickel deposition compared to the sulfate-based nickel solution. The rate of deposition increased with increasing the solution flow velocity from 1.5 to 3 m/s and raising current density from 0.4 × 104 to 1.6 × 10 4 A/m2 for both solution baths. Adhesion test indicated good level of adhesion between the deposited nickel and titanium surface. The bonding toughness increased to 4 J/m2 for 1.2 × 104 A/m2 as a result of higher deposition rate. However, the mechanism responsible for the coating process was discussed in detail.

Food Policy, 1990

... Policy measures need to be urgently instituted to redress this balance through the provision ... more ... Policy measures need to be urgently instituted to redress this balance through the provision of in frastructures, services and recreation FOOD POLICY June 1990 191 VIEWPOINT MA Hussain and P. Lunven, 'Urbaniza tion and hunger in the cities', Food and Nutrition Bulletin ...

Computational Materials Science, 2012

Abstract The mechanical properties and mechanics of aluminum/nickel (Al/Ni) and Ni/Al multilayers... more Abstract The mechanical properties and mechanics of aluminum/nickel (Al/Ni) and Ni/Al multilayers under the three-point nanobending test are studied using Molecular Dynamics (MDs) simulations based on the many-body tight-binding potential. The effects of the thickness of individual layers and temperature are evaluated in terms of molecular trajectories, loading force, adhesion force, von Mises stress, slip vectors, and elastic recovery ratio. Simulation results show that the bending angle of a multilayer increases with decreasing hardness of its surface layer. Alloying phenomena occur frequently on a deformed multilayer whose surface layer hardness is much higher than that of the layer below. The internal stress of a multilayer increases with increasing indentation depth and temperature, and the required loading force and the adhesion force decrease with increasing temperature. For multilayers with a thickness of only several nanometers, the variation of mechanical strength with increasing number of layers (decreasing thickness of layers) mainly depends on the hardness ratio of the surface layer to the layer below. The elastic recovery increases with increasing atomic bonding energy and temperature.

Carbon, 2006

Carbon nanotube (CNT) reinforced hydroxyapatite composite coatings have been successfully fabrica... more Carbon nanotube (CNT) reinforced hydroxyapatite composite coatings have been successfully fabricated by laser surface alloying. The phase compositions and the microstructure of the composite coatings were studied using X-ray diffraction, scanning electron microscopy, transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM). TEM observation showed that a large amount of CNTs can be found with their original tubular morphology in the composite coatings, even though some CNTs react with titanium element in the substrate during laser irradiation. Additionally, measurement on the elastic modulus, hardness of the composite coatings by nanoindentation tests indicated that the mechanical properties are affected by the amount of CNTs in the starting precursor materials. Therefore, CNT reinforced hydroxyapatite composite coating is a promising coating material for high-load-bearing metal implants.

Biomaterials, 2007

This article was originally published in a journal published by Elsevier, and the attached copy i... more This article was originally published in a journal published by Elsevier, and the attached copy is provided by Elsevier for the author's benefit and for the benefit of the author's institution, for non-commercial research and educational use including without limitation use in instruction at your institution, sending it to specific colleagues that you know, and providing a copy to your institution's administrator.

Applied Mechanics and Materials, 2013

Diamond coating on tungsten carbide (WC-Co) cutting tools with cobalt binder experiences delamina... more Diamond coating on tungsten carbide (WC-Co) cutting tools with cobalt binder experiences delaminating failure due to the deleterious effect of cobalt. One of the methods used to reduce this effect is by coating an interlayer onto the substrate surface prior to diamond deposition. Different materials have been used as an interlayer which is normally deposited to the substrate surface using CVD and PVD techniques. Among different materials used as interlayer on WC-Co, nickel is considered as an attractive candidate due its good chemical and physical properties. In this study the potential of the electroplating technique for deposition of nickel interlayer on WC-Co will be investigated. Nickel deposition on WC-6%Co substrate was carried out by electroplating in a standard watts solution at constant plating parameters (Current: 0.1 Amp, electric potential: 1.0 V and pH: 3.5). The gap between anode and cathode was varied (5mm, 10mm and 15mm). The nickel coating formed on the hard metal s...

The cytotoxicity of carbon nanotubes (CNTs) is a major concern today well before its unusual phys... more The cytotoxicity of carbon nanotubes (CNTs) is a major concern today well before its unusual physicochemical, mechanical, and electrical properties are fully exploited for commercial interests and subsequent mass production leading to greater possibilities for its exposure to humans and the environment. Contradictory reports on cytotoxicity of CNTs often appear in the literature and a mechanistic explanation of the reported toxicity remains obscure. We review here the conflicting results to focus categorically on an array of issues in CNT cytotoxicity. They include dispersion, aggregation status, coating or functionalization and immobilization, cellular uptake or internalization, purity in terms of metal catalyst contaminants, size and size distribution, surface area, surface chemistry and surface reactivity, cell types selected for experimentation as well as bioassay of nanotoxicity itself attesting as an issue in cytotoxicity. Recently a general agreement has emerged towards the potential toxicity of CNTs, although various paradigms explaining the mechanisms of CNT cytotoxicity continue to be elusive in the literature. A lack of synergy among various issues while studying cytotoxicity and most developed paradigms for the mechanism of CNT toxicity is highlighted.

AIDS Research and Human Retroviruses, 2005

The human immunodeficiency virus type 1 (HIV-1) rev exons 1 and 2 sequences were analyzed from si... more The human immunodeficiency virus type 1 (HIV-1) rev exons 1 and 2 sequences were analyzed from six mother-infant pairs following perinatal transmission. The rev open reading frame was maintained with a frequency of 93.96% in six mother-infant pairs' sequences. There was a low degree of viral heterogeneity and estimates of genetic diversity in mother-infant pairs' rev sequences. However, the distances of rev sequences between epidemiologically unlinked individuals were greater than in epidemiologically linked mother-infant pairs. Furthermore, phylogenetic parameters revealed that the epidemiologically linked mother-infant pairs were closer evolutionarily to each other as compared with epidemiologically unlinked mother-infant pairs. Both mothers and infants were under positive selection pressure as determined by the ratios of nonsynonymous to synonymous substitutions. The functional domains required for Rev activity, including nuclear export of RNA, RNA binding domain, and nuclear import signals, were conserved in all mother-infant pairs' sequences. The conservation of functional domains of rev and a low degree of heterogeneity following vertical transmission are consistent with an indispensable role of rev in the HIV-1 life cycle.

Advances in Materials Science and Engineering, 2013

Hot corrosion behavior of yttria stabilized zirconia (YSZ), YSZ/normal Al2O3, and YSZ/nano-Al2O3c... more Hot corrosion behavior of yttria stabilized zirconia (YSZ), YSZ/normal Al2O3, and YSZ/nano-Al2O3coatings was investigated in the presence of molten mixture of Na2SO4 + V2O5at 1000°C. Microstructural characterization showed that the creation of hot corrosion products containing YVO4crystals and monoclinic ZrO2is primarily related to the reaction between NaVO3and Y2O3during hot corrosion. The lowest amount of hot corrosion products was observed in YSZ as an inner layer of YSZ/nano-Al2O3coating. Hence, it can be concluded that the presence of nanostructured Al2O3layer over the conventional YSZ coating can considerably reduce the infiltration of molten corrosive salts into the YSZ layer during hot corrosion which is mainly related to the compactness of nanostructured alumina layer (including nanoregions) in comparison with normal alumina layer.

The Lancet, 2021

Background Azithromycin has been proposed as a treatment for COVID-19 on the basis of its immunom... more Background Azithromycin has been proposed as a treatment for COVID-19 on the basis of its immunomodulatory actions. We aimed to evaluate the safety and efficacy of azithromycin in patients admitted to hospital with COVID-19. Methods In this randomised, controlled, open-label, adaptive platform trial (Randomised Evaluation of COVID-19 Therapy [RECOVERY]), several possible treatments were compared with usual care in patients admitted to hospital with COVID-19 in the UK. The trial is underway at 176 hospitals in the UK. Eligible and consenting patients were randomly allocated to either usual standard of care alone or usual standard of care plus azithromycin 500 mg once per day by mouth or intravenously for 10 days or until discharge (or allocation to one of the other RECOVERY treatment groups). Patients were assigned via web-based simple (unstratified) randomisation with allocation concealment and were twice as likely to be randomly assigned to usual care than to any of the active treatment groups. Participants and local study staff were not masked to the allocated treatment, but all others involved in the trial were masked to the outcome data during the trial. The primary outcome was 28-day all-cause mortality, assessed in the intention-to-treat population. The trial is registered with ISRCTN, 50189673, and ClinicalTrials.gov, NCT04381936. Findings Between April 7 and Nov 27, 2020, of 16 442 patients enrolled in the RECOVERY trial, 9433 (57%) were eligible and 7763 were included in the assessment of azithromycin. The mean age of these study participants was 65•3 years (SD 15•7) and approximately a third were women (2944 [38%] of 7763). 2582 patients were randomly allocated to receive azithromycin and 5181 patients were randomly allocated to usual care alone. Overall, 561 (22%) patients allocated to azithromycin and 1162 (22%) patients allocated to usual care died within 28 days (rate ratio 0•97, 95% CI 0•87-1•07; p=0•50). No significant difference was seen in duration of hospital stay (median 10 days [IQR 5 to >28] vs 11 days [5 to >28]) or the proportion of patients discharged from hospital alive within 28 days (rate ratio 1•04, 95% CI 0•98-1•10; p=0•19). Among those not on invasive mechanical ventilation at baseline, no significant difference was seen in the proportion meeting the composite endpoint of invasive mechanical ventilation or death (risk ratio 0•95, 95% CI 0•87-1•03; p=0•24). Interpretation In patients admitted to hospital with COVID-19, azithromycin did not improve survival or other prespecified clinical outcomes. Azithromycin use in patients admitted to hospital with COVID-19 should be restricted to patients in whom there is a clear antimicrobial indication.

Clinical Hemorheology and Microcirculation, 1996

Clinical Hemorheology and Microcirculation, 1995

ABSTRACT

Proceedings of 16th Annual International Conference of the IEEE Engineering in Medicine and Biology Society

ABSTRACT

The terrestrial surface is confronting the jeopardy, facing the havoc and combating the atrocity ... more The terrestrial surface is confronting the jeopardy, facing the havoc and combating the atrocity of price hike that is worsening its social and economic spheres while bringing obnoxious results to the social stability and national development of the subject vulnerable masses. This study was conducted in District Swat, Khyber Pakhtunkhwa province of Pakistan, which evidently describes the socioeconomic and psychological impacts of price hike on low-income households. Data was collected from 180 respondents of low-income households of the 4 Union Councils (Tehsil Matta) that were purposively selected through cluster sampling technique using interview schedule. The collected data has been assessed with the application of Chi-square test followed by tabular presentation in support with bar-charts, which have further been discussed on the basis of findings and results. The results show that price hike being a critical and sizzling phenomenon has numerous consequences upon the socioeconomic and psychological well-being of low-income households, which demoralize their overall prosperity. The study strongly recommends awareness among masses, need based planning and practice of proper policy, confrontation and penalty to the misdemeanors and hoarders, and remunerative role of mass media are foreseeable that may bring assistance in alleviation of the curses of price hike.

Corporal punishment is one of the hazardous aspects in educational course of an individual/studen... more Corporal punishment is one of the hazardous aspects in educational course of an individual/student that is persevering to vacate the roots of personality development and academic career of the subject students. This study describes The Impacts of Corporal Punishment on Students' Academic Career and Personality Development up-to Secondary Level Education. The study was conducted in Chakdara town and adjacent areas of District Dir (Lower), Khyber Pakhtunkhwa, Pakistan. Data was collected from 360 respondents of primary and high schools' students using stratified random sampling technique through proportional allocation method using interview schedule. The data was analyzed by applying Chi-square test and processed in the form of tables, while discussions have been made on the basis of findings and results. The results show that corporal punishment has multidimensional impacts upon students' academic performance/career, psyche and personality development. The study suggests that teachers' education, training and awareness regarding curbing ways of corporal punishment and adopting alternative ways to correct students' misbehavior is inevitable.

Ultrasonic imaging, 2012

In ultrasound elastography, the strain in compressed tissue due to external deformation is estima... more In ultrasound elastography, the strain in compressed tissue due to external deformation is estimated and is smaller in harder than softer tissue. With increased stress, the nonaxial motions of tissue elements increase and result in noisier strain images. At high strain, the envelope of the rf signal exhibits robustness to signal decorrelation. However, the precision of strain estimates using envelope signals is much worse compared to that using the rf signals. In this paper, we propose a novel approach for robust strain estimation by combining weighted rf cross-correlation and envelope cross-correlation functions. An applied strain-dependent piecewise-linear-weight is used for this purpose. In addition, we introduce nonlinear diffusion filtering to further enhance the resulting strain image. The results of our algorithm are demonstrated for up to 10% applied strain using a finite-element modelling (FEM) simulation phantom. It reveals that the elastographic signal-to-noise ratio (SNR...

International Journal of Nanomanufacturing, 2010

This paper describes the application of electroforming in the synthesis of nanocrystalline nickel... more This paper describes the application of electroforming in the synthesis of nanocrystalline nickel by very high speed movement of the electrolyte; the principles and mechanisms of electroforming in the production of nanocrystalline structured metallic objects in combination with high speed movement of electrolyte are also described. Nanocrystalline nickel components were formed at a speed exceeding 600 µm per hour; the grain size of the electrodeposited nickel was considerably reduced by high speed movement of the plating solution. When requirements specify high-tolerances, complexity, lightweight and miniature geometry, electroforming is a serious contender and in certain cases may be the only economically viable manufacturing process. AFM characterisation showed that the crystalline/particle sizes of the electroformed objects were less than 30 nm. The nickel deposits were characterised further using SEM/EDAX. The focus of this study is primarily in the application of nanomaterials in industrial gas turbines.

International Journal of Nanoparticles, 2009

ABSTRACT

Micron, 2004

The platelet membrane receptor a IIb b 3 binds to adsorbed protein ligands including fibrinogen, ... more The platelet membrane receptor a IIb b 3 binds to adsorbed protein ligands including fibrinogen, von Willebrand factor and fibronectin, and is critically important in mediating platelet adhesion to damaged subendothelium and to synthetic biomaterial surfaces. This receptor is a member of the integrin family, a highly prevalent class of heterodimeric molecules consisting of a single a and b subunit. In an ongoing effort to understand the mechanisms underlying platelet adhesion events, high-resolution atomic force microscopy (AFM) under dynamic conditions was used to obtain images of a IIb b 3 molecules as well as aggregates of the protein. Images of integrin molecules were obtained by tapping mode AFM under aqueous buffer conditions following adsorption on a series of ultrasmooth model surfaces. On a model hydrophobic surface, detergents stabilizing the protein in solution competed for surface adsorption sites. When this detergent was removed from the system, the protein was predominantly seen as aggregates with head groups pointing outward. A limited number of individual integrin molecules were observed, and were found to have dimensions consistent with those reported previously by electron microscopy studies. Integrin molecules showed weak adhesion to the two hydrophilic surfaces used in the study, although formation of a lipid bilayer around surface-adsorbed molecules improved the resolution. At longer time periods, the integrin molecules embedded in this lipid bilayer exhibited sufficient mobility to form molecular aggregates. The structural measurements described in this study not only reveal threedimensional features of the molecule, they represent an important step towards dynamic adsorption experiments and visualizing the integrin interacting with surface-adsorbed proteins as in biomaterial-induced thrombogenesis.

Journal of Materials Engineering and Performance, 2012

An innovative process has been developed for electroplating of nickel on titanium surface using f... more An innovative process has been developed for electroplating of nickel on titanium surface using fast solution flow technique. Nickel was directly deposited on a titanium alloy without using any pretreatment process. Level of adhesion was determined using quantitative peel test and characterization of the deposition was performed by scanning electron microscopy. Results showed that the rate of nickel deposition at 60 C was higher than that of the rate of nickel deposition at 40 C. Moreover, Watts solution provided higher rate of nickel deposition compared to the sulfate-based nickel solution. The rate of deposition increased with increasing the solution flow velocity from 1.5 to 3 m/s and raising current density from 0.4 × 104 to 1.6 × 10 4 A/m2 for both solution baths. Adhesion test indicated good level of adhesion between the deposited nickel and titanium surface. The bonding toughness increased to 4 J/m2 for 1.2 × 104 A/m2 as a result of higher deposition rate. However, the mechanism responsible for the coating process was discussed in detail.

Food Policy, 1990

... Policy measures need to be urgently instituted to redress this balance through the provision ... more ... Policy measures need to be urgently instituted to redress this balance through the provision of in frastructures, services and recreation FOOD POLICY June 1990 191 VIEWPOINT MA Hussain and P. Lunven, 'Urbaniza tion and hunger in the cities', Food and Nutrition Bulletin ...

Computational Materials Science, 2012

Abstract The mechanical properties and mechanics of aluminum/nickel (Al/Ni) and Ni/Al multilayers... more Abstract The mechanical properties and mechanics of aluminum/nickel (Al/Ni) and Ni/Al multilayers under the three-point nanobending test are studied using Molecular Dynamics (MDs) simulations based on the many-body tight-binding potential. The effects of the thickness of individual layers and temperature are evaluated in terms of molecular trajectories, loading force, adhesion force, von Mises stress, slip vectors, and elastic recovery ratio. Simulation results show that the bending angle of a multilayer increases with decreasing hardness of its surface layer. Alloying phenomena occur frequently on a deformed multilayer whose surface layer hardness is much higher than that of the layer below. The internal stress of a multilayer increases with increasing indentation depth and temperature, and the required loading force and the adhesion force decrease with increasing temperature. For multilayers with a thickness of only several nanometers, the variation of mechanical strength with increasing number of layers (decreasing thickness of layers) mainly depends on the hardness ratio of the surface layer to the layer below. The elastic recovery increases with increasing atomic bonding energy and temperature.

Carbon, 2006

Carbon nanotube (CNT) reinforced hydroxyapatite composite coatings have been successfully fabrica... more Carbon nanotube (CNT) reinforced hydroxyapatite composite coatings have been successfully fabricated by laser surface alloying. The phase compositions and the microstructure of the composite coatings were studied using X-ray diffraction, scanning electron microscopy, transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM). TEM observation showed that a large amount of CNTs can be found with their original tubular morphology in the composite coatings, even though some CNTs react with titanium element in the substrate during laser irradiation. Additionally, measurement on the elastic modulus, hardness of the composite coatings by nanoindentation tests indicated that the mechanical properties are affected by the amount of CNTs in the starting precursor materials. Therefore, CNT reinforced hydroxyapatite composite coating is a promising coating material for high-load-bearing metal implants.

Biomaterials, 2007

This article was originally published in a journal published by Elsevier, and the attached copy i... more This article was originally published in a journal published by Elsevier, and the attached copy is provided by Elsevier for the author's benefit and for the benefit of the author's institution, for non-commercial research and educational use including without limitation use in instruction at your institution, sending it to specific colleagues that you know, and providing a copy to your institution's administrator.

Applied Mechanics and Materials, 2013

Diamond coating on tungsten carbide (WC-Co) cutting tools with cobalt binder experiences delamina... more Diamond coating on tungsten carbide (WC-Co) cutting tools with cobalt binder experiences delaminating failure due to the deleterious effect of cobalt. One of the methods used to reduce this effect is by coating an interlayer onto the substrate surface prior to diamond deposition. Different materials have been used as an interlayer which is normally deposited to the substrate surface using CVD and PVD techniques. Among different materials used as interlayer on WC-Co, nickel is considered as an attractive candidate due its good chemical and physical properties. In this study the potential of the electroplating technique for deposition of nickel interlayer on WC-Co will be investigated. Nickel deposition on WC-6%Co substrate was carried out by electroplating in a standard watts solution at constant plating parameters (Current: 0.1 Amp, electric potential: 1.0 V and pH: 3.5). The gap between anode and cathode was varied (5mm, 10mm and 15mm). The nickel coating formed on the hard metal s...

The cytotoxicity of carbon nanotubes (CNTs) is a major concern today well before its unusual phys... more The cytotoxicity of carbon nanotubes (CNTs) is a major concern today well before its unusual physicochemical, mechanical, and electrical properties are fully exploited for commercial interests and subsequent mass production leading to greater possibilities for its exposure to humans and the environment. Contradictory reports on cytotoxicity of CNTs often appear in the literature and a mechanistic explanation of the reported toxicity remains obscure. We review here the conflicting results to focus categorically on an array of issues in CNT cytotoxicity. They include dispersion, aggregation status, coating or functionalization and immobilization, cellular uptake or internalization, purity in terms of metal catalyst contaminants, size and size distribution, surface area, surface chemistry and surface reactivity, cell types selected for experimentation as well as bioassay of nanotoxicity itself attesting as an issue in cytotoxicity. Recently a general agreement has emerged towards the potential toxicity of CNTs, although various paradigms explaining the mechanisms of CNT cytotoxicity continue to be elusive in the literature. A lack of synergy among various issues while studying cytotoxicity and most developed paradigms for the mechanism of CNT toxicity is highlighted.

AIDS Research and Human Retroviruses, 2005

The human immunodeficiency virus type 1 (HIV-1) rev exons 1 and 2 sequences were analyzed from si... more The human immunodeficiency virus type 1 (HIV-1) rev exons 1 and 2 sequences were analyzed from six mother-infant pairs following perinatal transmission. The rev open reading frame was maintained with a frequency of 93.96% in six mother-infant pairs' sequences. There was a low degree of viral heterogeneity and estimates of genetic diversity in mother-infant pairs' rev sequences. However, the distances of rev sequences between epidemiologically unlinked individuals were greater than in epidemiologically linked mother-infant pairs. Furthermore, phylogenetic parameters revealed that the epidemiologically linked mother-infant pairs were closer evolutionarily to each other as compared with epidemiologically unlinked mother-infant pairs. Both mothers and infants were under positive selection pressure as determined by the ratios of nonsynonymous to synonymous substitutions. The functional domains required for Rev activity, including nuclear export of RNA, RNA binding domain, and nuclear import signals, were conserved in all mother-infant pairs' sequences. The conservation of functional domains of rev and a low degree of heterogeneity following vertical transmission are consistent with an indispensable role of rev in the HIV-1 life cycle.

Advances in Materials Science and Engineering, 2013

Hot corrosion behavior of yttria stabilized zirconia (YSZ), YSZ/normal Al2O3, and YSZ/nano-Al2O3c... more Hot corrosion behavior of yttria stabilized zirconia (YSZ), YSZ/normal Al2O3, and YSZ/nano-Al2O3coatings was investigated in the presence of molten mixture of Na2SO4 + V2O5at 1000°C. Microstructural characterization showed that the creation of hot corrosion products containing YVO4crystals and monoclinic ZrO2is primarily related to the reaction between NaVO3and Y2O3during hot corrosion. The lowest amount of hot corrosion products was observed in YSZ as an inner layer of YSZ/nano-Al2O3coating. Hence, it can be concluded that the presence of nanostructured Al2O3layer over the conventional YSZ coating can considerably reduce the infiltration of molten corrosive salts into the YSZ layer during hot corrosion which is mainly related to the compactness of nanostructured alumina layer (including nanoregions) in comparison with normal alumina layer.

The Lancet, 2021

Background Azithromycin has been proposed as a treatment for COVID-19 on the basis of its immunom... more Background Azithromycin has been proposed as a treatment for COVID-19 on the basis of its immunomodulatory actions. We aimed to evaluate the safety and efficacy of azithromycin in patients admitted to hospital with COVID-19. Methods In this randomised, controlled, open-label, adaptive platform trial (Randomised Evaluation of COVID-19 Therapy [RECOVERY]), several possible treatments were compared with usual care in patients admitted to hospital with COVID-19 in the UK. The trial is underway at 176 hospitals in the UK. Eligible and consenting patients were randomly allocated to either usual standard of care alone or usual standard of care plus azithromycin 500 mg once per day by mouth or intravenously for 10 days or until discharge (or allocation to one of the other RECOVERY treatment groups). Patients were assigned via web-based simple (unstratified) randomisation with allocation concealment and were twice as likely to be randomly assigned to usual care than to any of the active treatment groups. Participants and local study staff were not masked to the allocated treatment, but all others involved in the trial were masked to the outcome data during the trial. The primary outcome was 28-day all-cause mortality, assessed in the intention-to-treat population. The trial is registered with ISRCTN, 50189673, and ClinicalTrials.gov, NCT04381936. Findings Between April 7 and Nov 27, 2020, of 16 442 patients enrolled in the RECOVERY trial, 9433 (57%) were eligible and 7763 were included in the assessment of azithromycin. The mean age of these study participants was 65•3 years (SD 15•7) and approximately a third were women (2944 [38%] of 7763). 2582 patients were randomly allocated to receive azithromycin and 5181 patients were randomly allocated to usual care alone. Overall, 561 (22%) patients allocated to azithromycin and 1162 (22%) patients allocated to usual care died within 28 days (rate ratio 0•97, 95% CI 0•87-1•07; p=0•50). No significant difference was seen in duration of hospital stay (median 10 days [IQR 5 to >28] vs 11 days [5 to >28]) or the proportion of patients discharged from hospital alive within 28 days (rate ratio 1•04, 95% CI 0•98-1•10; p=0•19). Among those not on invasive mechanical ventilation at baseline, no significant difference was seen in the proportion meeting the composite endpoint of invasive mechanical ventilation or death (risk ratio 0•95, 95% CI 0•87-1•03; p=0•24). Interpretation In patients admitted to hospital with COVID-19, azithromycin did not improve survival or other prespecified clinical outcomes. Azithromycin use in patients admitted to hospital with COVID-19 should be restricted to patients in whom there is a clear antimicrobial indication.

Clinical Hemorheology and Microcirculation, 1996

Clinical Hemorheology and Microcirculation, 1995

ABSTRACT

Proceedings of 16th Annual International Conference of the IEEE Engineering in Medicine and Biology Society

ABSTRACT

The terrestrial surface is confronting the jeopardy, facing the havoc and combating the atrocity ... more The terrestrial surface is confronting the jeopardy, facing the havoc and combating the atrocity of price hike that is worsening its social and economic spheres while bringing obnoxious results to the social stability and national development of the subject vulnerable masses. This study was conducted in District Swat, Khyber Pakhtunkhwa province of Pakistan, which evidently describes the socioeconomic and psychological impacts of price hike on low-income households. Data was collected from 180 respondents of low-income households of the 4 Union Councils (Tehsil Matta) that were purposively selected through cluster sampling technique using interview schedule. The collected data has been assessed with the application of Chi-square test followed by tabular presentation in support with bar-charts, which have further been discussed on the basis of findings and results. The results show that price hike being a critical and sizzling phenomenon has numerous consequences upon the socioeconomic and psychological well-being of low-income households, which demoralize their overall prosperity. The study strongly recommends awareness among masses, need based planning and practice of proper policy, confrontation and penalty to the misdemeanors and hoarders, and remunerative role of mass media are foreseeable that may bring assistance in alleviation of the curses of price hike.

Corporal punishment is one of the hazardous aspects in educational course of an individual/studen... more Corporal punishment is one of the hazardous aspects in educational course of an individual/student that is persevering to vacate the roots of personality development and academic career of the subject students. This study describes The Impacts of Corporal Punishment on Students' Academic Career and Personality Development up-to Secondary Level Education. The study was conducted in Chakdara town and adjacent areas of District Dir (Lower), Khyber Pakhtunkhwa, Pakistan. Data was collected from 360 respondents of primary and high schools' students using stratified random sampling technique through proportional allocation method using interview schedule. The data was analyzed by applying Chi-square test and processed in the form of tables, while discussions have been made on the basis of findings and results. The results show that corporal punishment has multidimensional impacts upon students' academic performance/career, psyche and personality development. The study suggests that teachers' education, training and awareness regarding curbing ways of corporal punishment and adopting alternative ways to correct students' misbehavior is inevitable.

Ultrasonic imaging, 2012

In ultrasound elastography, the strain in compressed tissue due to external deformation is estima... more In ultrasound elastography, the strain in compressed tissue due to external deformation is estimated and is smaller in harder than softer tissue. With increased stress, the nonaxial motions of tissue elements increase and result in noisier strain images. At high strain, the envelope of the rf signal exhibits robustness to signal decorrelation. However, the precision of strain estimates using envelope signals is much worse compared to that using the rf signals. In this paper, we propose a novel approach for robust strain estimation by combining weighted rf cross-correlation and envelope cross-correlation functions. An applied strain-dependent piecewise-linear-weight is used for this purpose. In addition, we introduce nonlinear diffusion filtering to further enhance the resulting strain image. The results of our algorithm are demonstrated for up to 10% applied strain using a finite-element modelling (FEM) simulation phantom. It reveals that the elastographic signal-to-noise ratio (SNR...