pawan sharma - Academia.edu (original) (raw)
Papers by pawan sharma
Heat and Mass Transfer, 2003
The problem of three dimensional unsteady convection flow through a porous medium, with effect of... more The problem of three dimensional unsteady convection flow through a porous medium, with effect of mass transfer bounded by an infinite vertical porous plate is discussed, when the suction at the plate is transverse sinusoidal and the plate temperature oscillates in time about a constant mean. Assuming the free stream velocity to be uniform, approximate solutions are obtained for the flow field, the temperature field, the skin-friction and the rate of heat transfer. The dependence of solution on Pr (Prandtl number), Gr (Grashof number based on temperature), Gc (modified Grashof number based on concentration difference), Sc (Schimdt number), the frequency and the permeability parameter is also investigated.
Journal of Dr. NTR University of Health Sciences, Jan 10, 2014
Truck drivers in India suffer from multiple health problems related to their long travelling and ... more Truck drivers in India suffer from multiple health problems related to their long travelling and inadequate rest hours. The objective was to study the health problems and risk factors in a sample of truck drivers in Hyderabad city. A cross-sectional study was conducted during June 2011 among 59 truck drivers from a transport company, who were interviewed using a pretested proforma and examined by trained investigators. Lab results and medical consultations were provided the following day. Results were analyzed using Microsoft Access software. The mean age of truck drivers was 28.46 ± 9.3 years. 54% suffered from low backache, 16.95% from visual problems, 45.76% had hypertension, 8.47% had anemia and 30.51% had high-risk body mass index. The prevalence of risk factors for metabolic disorders was lower compared to the general population. Proper road and job policies for truck drivers should be framed, aiming at subjecting them for periodic health evaluations to detect the diseases early.
Heat Transfer Research, 2009
Journal of the Neurological Sciences, 2011
Acute dengue myositis is characterized by fever and myalgia (with or without muscle weakness). Th... more Acute dengue myositis is characterized by fever and myalgia (with or without muscle weakness). The 7 cases of acute dengue myositis were retrospectively evaluated in the present study. Dengue myositis was diagnosed on the basis of a clinical picture consistent with the infection, elevated creatine phosphokinase, normal CSF, positive serum IgM for dengue virus, and the exclusion of other causes. The mean age of patients was 19.4 (range 3-40) years. Majority (5) of the patients were male. In our series 3 of the cases suffered from fulminant myositis. They were characterized by generalized weaknesses which included the respiratory muscles. All the 3 patients had markedly elevated creatine phosphokinase levels (ranging from 16,590 to 117,200 IU/L). Two patients suffering from fulminant myositis required mechanical ventilation. However, they succumbed to their illnesses. The third patient showed signs of improvement. One case had paraparesis and an elevated creatine phosphokinase level. However, a spontaneous complete recovery was observed. The remaining 3 cases had quadriparesis with trunk and neck weaknesses, sparing of respiratory muscles, creatine phosphokinase levels up to 3000 U/L. However, a complete recovery was observed in these patients within 4 weeks. To conclude, early respiratory involvement, high creatine phosphokinase values, and severe myalgia suggest a severe form of dengue myositis.
Journal of Porous Media, 2005
Journal of Clinical Neuroscience, 2011
Subacute sclerosing panencephalitis (SSPE) is a progressive, devastating neurologic disorder caus... more Subacute sclerosing panencephalitis (SSPE) is a progressive, devastating neurologic disorder caused by mutant measles virus. In this study we evaluated the prognostic value of neuroimaging abnormalities in SSPE. Thirty consecutive patients with SSPE were included. Diagnosis of SSPE was based on the criteria described by Dyken. Patients were followed for 6 months. Neuroimaging studies were performed at inclusion and after 6 months. Regression or progression of the disease was defined as a change of one, or more than one, stage in Jabbour's staging system. Degree of disability was assessed using the modified Rankin scale (mRS) score. Neuroimaging abnormalities were seen in 27 patients. Dominant imaging abnormalities were cerebral atrophy, white matter signal changes, cortical grey matter abnormalities and signal change in the basal ganglia. After 6 months of follow-up, 18 (60%) patients had a poor outcome (mRS score: 3-6); one patient died. The remaining 12 patients (40%) had a stabilized clinical condition (mRS score: 0-2). On univariate analysis, predictors of death or disability were: poor mRS score at baseline (p = 0.003) and Jabbour's clinical stage III (p = 0.019). None of the neuroimaging abnormalities were associated with a poor prognosis or clinical deterioration (p > 0.05). We conclude that we did not observe any association between cerebral neuroimaging at baseline and neurological outcome after 6 months in patients with SSPE.
Journal of Bodywork and Movement Therapies, 2012
The role of the brain in post-stroke gait is not understood properly, although the ability to wal... more The role of the brain in post-stroke gait is not understood properly, although the ability to walk becomes impaired in more than 80% of post-stroke patients. Most, however, regain some ability to walk with either limited mobility or inefficient, asymmetrical or unsafe gait. Conventional intervention focuses on support of weak muscles or body part by use of foot orthosis and walking aids. This review provides an overview of available evidence of neurokinesiology & neurophysiology of normal and post-stroke gait. The role of the spinal cord has been explored, more in animals than humans. Mammalian locomotion is based on a rhythmic, "pacemaker" activity of the spinal stepping generators. Bipedal human locomotion is different from quadripedal animal locomotion. However, knowledge derived from the spinal cord investigation of animals, is being applied for management of human gait dysfunction. The potential role of the brain is now recognized in the independent activation of muscles during walking. The brain modifies the gait pattern during the complex demands of daily activities. Though the exact role of the motor cortex in control of gait is unclear, available evidence may be applied to gait rehabilitation of post-stroke patients. ª
International Journal of Mathematics and Mathematical Sciences, 2004
Page 1. ...
International Journal of Heat and Mass Transfer, 2009
Finite element simulations have been performed to investigate the influence of linearly heated si... more Finite element simulations have been performed to investigate the influence of linearly heated side wall(s) or cooled right wall on mixed convection lid-driven flows in a square cavity. It is interesting to note that multiple circulation cells appear inside the cavity with the increase of Pr for Re ¼ 10 and Gr ¼ 10 5 in the case of linearly heated side walls. For Pr ¼ 0:015, only two circulation cells are formed inside the cavity. As Pr increases to 0.7, three circulation cells are formed inside the cavity. Further increase in Pr to 10, leads to the formation of four circulation cells inside the cavity. On the other hand, only two circulation cells are formed inside the cavity for the case of cooled right wall. A detailed analysis of flow pattern shows that as the value of Re increases from 1 to 10 2 , there occurs a transition from natural convection to forced convection depending on the value of Gr irrespective of Pr. It is observed that the secondary vortex at the top left corner disappears for Re ¼ 10 2 and Gr ¼ 10 5 due to enhanced motion of the upper lid in the case of cooled right wall while a small secondary vortex exist at the bottom right corner in the case of linearly heated side walls. The local Nusselt number (Nu b ) plot shows that heat transfer rate is equal to 1 at the edges for the case of linearly heated side walls case and that is zero at the left edge and thereafter that increases for the case of cooled right wall. It is interesting to observe that Nu b is large within 0:4 6 X 6 0:6 due to compression of isotherms for Pr ¼ 0:7 and 10 in the case of linearly heated side wall. It is also observed that Nu r or Nu l exhibits oscillations especially for Pr ¼ 10 at higher Gr due to the presence of multiple circulations. It is also observed that Nu r or Nu l vs Gr plots show oscillation for two case studies. Average Nusselt numbers at the bottom and right walls are strong functions of Grashof number at larger Prandtl numbers whereas average Nusselt number at the left wall at a specific Pr is a weaker function of Gr.
Journal of Zhejiang University SCIENCE A, 2003
This paper reports research on the effects of variations in injection velocity and permeability o... more This paper reports research on the effects of variations in injection velocity and permeability on the heat transfer and flow through a highly porous medium between two horizontal parallel plates situated at constant distance with constant suction by the upper plate. Due to this type of variation in injection velocity and in permeability the flow becomes three dimensional. The governing equations are solved by adopting complex variable notations to obtain the expressions for the velocity and temperature field. The skin-friction along the main flow direction and rate of heat transfer are discussed with the help of graphs.
Pulmonary Pharmacology & Therapeutics, 2009
Clinical asthma is characterized by reversible airway obstruction which is commonly due to an exa... more Clinical asthma is characterized by reversible airway obstruction which is commonly due to an exaggerated airway narrowing referred to as airway hyperresponsiveness (AHR). Although debate exists on the complex etiology of AHR, it is clear that airway smooth muscle (ASM) mediated airway narrowing is a major contributor to airway dysfunction. More importantly, it is now appreciated that smooth muscle is far from being a simple cell with only contractile ability properties. Rather, it is more versatile with the capacity to exhibit numerous cellular functions as it adapts to the microenvironment to which it is exposed. The emerging ability of individual smooth muscle cells to undergo changes in their phenotype (phenotype plasticity) and function (functional plasticity) in response to physiological and pathological cues is an important and active area of research. This article provides a brief review of the current knowledge and emerging concepts in the field of ASM phenotype and function both under healthy and asthmatic conditions.
Organic & Biomolecular Chemistry, 2006
A 5&a... more A 5'-C-allylthymidine derivative was prepared from thymidine by the application of a stereoselective allylation procedure and its 5'(S)-configuration was confirmed. From this nucleoside derivative, appropriately protected building blocks were prepared and coupled using standard phosphoramidite chemistry to afford a dinucleotide with two 5'-C-allylgroups. This molecule was used as a substrate for a ring-closing metathesis (RCM) reaction and after deprotection, a 1 : 1 mixture of E- and Z-isomers of a cyclic dinucleotide with an unsaturated 5'-C-to-5'-C connection was obtained. Alternatively, a hydrogenation of the double bond and deprotection afforded a saturated cyclic dinucleotide. An advanced NMR-examination confirmed the constitution of this molecule and indicated a restriction in its overall conformational freedom. After variation of the protecting group strategy, a phosphoramidite building block of the saturated cyclic dinucleotide with the 5'-O-position protected as a pixyl ether and the phosphate protected as a methyl phosphotriester was obtained. This building block was used in the preparation of two 14-mer oligonucleotides with a central artificial bend due to the cyclic dinucleotide moiety. These were found to destabilise duplexes, slightly destabilise bulged duplexes but, to some extent, stabilise a three-way junction in high Mg(2+)-concentrations.
Nucleosides, Nucleotides and Nucleic Acids, 2007
A 3&a... more A 3'-C-branched LNA-type bicyclic nucleoside, containing a furanose ring locked in an N-type conformation, was synthesized from a known 3-C-vinyl allofuranose derivative using a strategy relying on the condensation with the nucleobase after the introduction of the branching hydroxymethyl chain by our recently developed RuO4 based protocol. This branched LNA nucleoside has a potential as a monomer for the functionalization of LNA.
Journal of Molecular Modeling, 2008
Aspartyl beta-semialdehyde dehydrogenase (ASADH) is an important enzyme, occupying the first bran... more Aspartyl beta-semialdehyde dehydrogenase (ASADH) is an important enzyme, occupying the first branch position of the biosynthetic pathway of the aspartate family of amino acids in bacteria, fungi and higher plants. It catalyses reversible dephosphorylation of L: -beta-aspartyl phosphate (betaAP) to L: -aspartate-beta-semialdehyde (ASA), a key intermediate in the biosynthesis of diaminopimelic acid (DAP)-an essential component of cross linkages in bacterial cell walls. Since the aspartate pathway is unique to plants and bacteria, and ASADH is the key enzyme in this pathway, it becomes an attractive target for antimicrobial agent development. Therefore, with the objective of deducing comparative structural models, we have described a molecular model emphasizing the uniqueness of ASADH from Mycobacterium tuberculosis (H37Rv) that should generate insights into the structural distinctiveness of this protein as compared to structurally resolved ASADH from other bacterial species. We find that mtASADH exhibits structural features common to bacterial ASADH, while other structural motifs are not present. Structural analysis of various domains in mtASADH reveals structural conservation among all bacterial ASADH proteins. The results suggest that the probable mechanism of action of the mtASADH enzyme might be same as that of other bacterial ASADH. Analysis of the structure of mtASADH will shed light on its mechanism of action and may help in designing suitable antagonists against this enzyme that could control the growth of Mycobacterium tuberculosis.
Journal of Chemical Research, 1997
Heat and Mass Transfer, 2003
The problem of three dimensional unsteady convection flow through a porous medium, with effect of... more The problem of three dimensional unsteady convection flow through a porous medium, with effect of mass transfer bounded by an infinite vertical porous plate is discussed, when the suction at the plate is transverse sinusoidal and the plate temperature oscillates in time about a constant mean. Assuming the free stream velocity to be uniform, approximate solutions are obtained for the flow field, the temperature field, the skin-friction and the rate of heat transfer. The dependence of solution on Pr (Prandtl number), Gr (Grashof number based on temperature), Gc (modified Grashof number based on concentration difference), Sc (Schimdt number), the frequency and the permeability parameter is also investigated.
Journal of Dr. NTR University of Health Sciences, Jan 10, 2014
Truck drivers in India suffer from multiple health problems related to their long travelling and ... more Truck drivers in India suffer from multiple health problems related to their long travelling and inadequate rest hours. The objective was to study the health problems and risk factors in a sample of truck drivers in Hyderabad city. A cross-sectional study was conducted during June 2011 among 59 truck drivers from a transport company, who were interviewed using a pretested proforma and examined by trained investigators. Lab results and medical consultations were provided the following day. Results were analyzed using Microsoft Access software. The mean age of truck drivers was 28.46 ± 9.3 years. 54% suffered from low backache, 16.95% from visual problems, 45.76% had hypertension, 8.47% had anemia and 30.51% had high-risk body mass index. The prevalence of risk factors for metabolic disorders was lower compared to the general population. Proper road and job policies for truck drivers should be framed, aiming at subjecting them for periodic health evaluations to detect the diseases early.
Heat Transfer Research, 2009
Journal of the Neurological Sciences, 2011
Acute dengue myositis is characterized by fever and myalgia (with or without muscle weakness). Th... more Acute dengue myositis is characterized by fever and myalgia (with or without muscle weakness). The 7 cases of acute dengue myositis were retrospectively evaluated in the present study. Dengue myositis was diagnosed on the basis of a clinical picture consistent with the infection, elevated creatine phosphokinase, normal CSF, positive serum IgM for dengue virus, and the exclusion of other causes. The mean age of patients was 19.4 (range 3-40) years. Majority (5) of the patients were male. In our series 3 of the cases suffered from fulminant myositis. They were characterized by generalized weaknesses which included the respiratory muscles. All the 3 patients had markedly elevated creatine phosphokinase levels (ranging from 16,590 to 117,200 IU/L). Two patients suffering from fulminant myositis required mechanical ventilation. However, they succumbed to their illnesses. The third patient showed signs of improvement. One case had paraparesis and an elevated creatine phosphokinase level. However, a spontaneous complete recovery was observed. The remaining 3 cases had quadriparesis with trunk and neck weaknesses, sparing of respiratory muscles, creatine phosphokinase levels up to 3000 U/L. However, a complete recovery was observed in these patients within 4 weeks. To conclude, early respiratory involvement, high creatine phosphokinase values, and severe myalgia suggest a severe form of dengue myositis.
Journal of Porous Media, 2005
Journal of Clinical Neuroscience, 2011
Subacute sclerosing panencephalitis (SSPE) is a progressive, devastating neurologic disorder caus... more Subacute sclerosing panencephalitis (SSPE) is a progressive, devastating neurologic disorder caused by mutant measles virus. In this study we evaluated the prognostic value of neuroimaging abnormalities in SSPE. Thirty consecutive patients with SSPE were included. Diagnosis of SSPE was based on the criteria described by Dyken. Patients were followed for 6 months. Neuroimaging studies were performed at inclusion and after 6 months. Regression or progression of the disease was defined as a change of one, or more than one, stage in Jabbour's staging system. Degree of disability was assessed using the modified Rankin scale (mRS) score. Neuroimaging abnormalities were seen in 27 patients. Dominant imaging abnormalities were cerebral atrophy, white matter signal changes, cortical grey matter abnormalities and signal change in the basal ganglia. After 6 months of follow-up, 18 (60%) patients had a poor outcome (mRS score: 3-6); one patient died. The remaining 12 patients (40%) had a stabilized clinical condition (mRS score: 0-2). On univariate analysis, predictors of death or disability were: poor mRS score at baseline (p = 0.003) and Jabbour's clinical stage III (p = 0.019). None of the neuroimaging abnormalities were associated with a poor prognosis or clinical deterioration (p > 0.05). We conclude that we did not observe any association between cerebral neuroimaging at baseline and neurological outcome after 6 months in patients with SSPE.
Journal of Bodywork and Movement Therapies, 2012
The role of the brain in post-stroke gait is not understood properly, although the ability to wal... more The role of the brain in post-stroke gait is not understood properly, although the ability to walk becomes impaired in more than 80% of post-stroke patients. Most, however, regain some ability to walk with either limited mobility or inefficient, asymmetrical or unsafe gait. Conventional intervention focuses on support of weak muscles or body part by use of foot orthosis and walking aids. This review provides an overview of available evidence of neurokinesiology & neurophysiology of normal and post-stroke gait. The role of the spinal cord has been explored, more in animals than humans. Mammalian locomotion is based on a rhythmic, "pacemaker" activity of the spinal stepping generators. Bipedal human locomotion is different from quadripedal animal locomotion. However, knowledge derived from the spinal cord investigation of animals, is being applied for management of human gait dysfunction. The potential role of the brain is now recognized in the independent activation of muscles during walking. The brain modifies the gait pattern during the complex demands of daily activities. Though the exact role of the motor cortex in control of gait is unclear, available evidence may be applied to gait rehabilitation of post-stroke patients. ª
International Journal of Mathematics and Mathematical Sciences, 2004
Page 1. ...
International Journal of Heat and Mass Transfer, 2009
Finite element simulations have been performed to investigate the influence of linearly heated si... more Finite element simulations have been performed to investigate the influence of linearly heated side wall(s) or cooled right wall on mixed convection lid-driven flows in a square cavity. It is interesting to note that multiple circulation cells appear inside the cavity with the increase of Pr for Re ¼ 10 and Gr ¼ 10 5 in the case of linearly heated side walls. For Pr ¼ 0:015, only two circulation cells are formed inside the cavity. As Pr increases to 0.7, three circulation cells are formed inside the cavity. Further increase in Pr to 10, leads to the formation of four circulation cells inside the cavity. On the other hand, only two circulation cells are formed inside the cavity for the case of cooled right wall. A detailed analysis of flow pattern shows that as the value of Re increases from 1 to 10 2 , there occurs a transition from natural convection to forced convection depending on the value of Gr irrespective of Pr. It is observed that the secondary vortex at the top left corner disappears for Re ¼ 10 2 and Gr ¼ 10 5 due to enhanced motion of the upper lid in the case of cooled right wall while a small secondary vortex exist at the bottom right corner in the case of linearly heated side walls. The local Nusselt number (Nu b ) plot shows that heat transfer rate is equal to 1 at the edges for the case of linearly heated side walls case and that is zero at the left edge and thereafter that increases for the case of cooled right wall. It is interesting to observe that Nu b is large within 0:4 6 X 6 0:6 due to compression of isotherms for Pr ¼ 0:7 and 10 in the case of linearly heated side wall. It is also observed that Nu r or Nu l exhibits oscillations especially for Pr ¼ 10 at higher Gr due to the presence of multiple circulations. It is also observed that Nu r or Nu l vs Gr plots show oscillation for two case studies. Average Nusselt numbers at the bottom and right walls are strong functions of Grashof number at larger Prandtl numbers whereas average Nusselt number at the left wall at a specific Pr is a weaker function of Gr.
Journal of Zhejiang University SCIENCE A, 2003
This paper reports research on the effects of variations in injection velocity and permeability o... more This paper reports research on the effects of variations in injection velocity and permeability on the heat transfer and flow through a highly porous medium between two horizontal parallel plates situated at constant distance with constant suction by the upper plate. Due to this type of variation in injection velocity and in permeability the flow becomes three dimensional. The governing equations are solved by adopting complex variable notations to obtain the expressions for the velocity and temperature field. The skin-friction along the main flow direction and rate of heat transfer are discussed with the help of graphs.
Pulmonary Pharmacology & Therapeutics, 2009
Clinical asthma is characterized by reversible airway obstruction which is commonly due to an exa... more Clinical asthma is characterized by reversible airway obstruction which is commonly due to an exaggerated airway narrowing referred to as airway hyperresponsiveness (AHR). Although debate exists on the complex etiology of AHR, it is clear that airway smooth muscle (ASM) mediated airway narrowing is a major contributor to airway dysfunction. More importantly, it is now appreciated that smooth muscle is far from being a simple cell with only contractile ability properties. Rather, it is more versatile with the capacity to exhibit numerous cellular functions as it adapts to the microenvironment to which it is exposed. The emerging ability of individual smooth muscle cells to undergo changes in their phenotype (phenotype plasticity) and function (functional plasticity) in response to physiological and pathological cues is an important and active area of research. This article provides a brief review of the current knowledge and emerging concepts in the field of ASM phenotype and function both under healthy and asthmatic conditions.
Organic & Biomolecular Chemistry, 2006
A 5&a... more A 5'-C-allylthymidine derivative was prepared from thymidine by the application of a stereoselective allylation procedure and its 5'(S)-configuration was confirmed. From this nucleoside derivative, appropriately protected building blocks were prepared and coupled using standard phosphoramidite chemistry to afford a dinucleotide with two 5'-C-allylgroups. This molecule was used as a substrate for a ring-closing metathesis (RCM) reaction and after deprotection, a 1 : 1 mixture of E- and Z-isomers of a cyclic dinucleotide with an unsaturated 5'-C-to-5'-C connection was obtained. Alternatively, a hydrogenation of the double bond and deprotection afforded a saturated cyclic dinucleotide. An advanced NMR-examination confirmed the constitution of this molecule and indicated a restriction in its overall conformational freedom. After variation of the protecting group strategy, a phosphoramidite building block of the saturated cyclic dinucleotide with the 5'-O-position protected as a pixyl ether and the phosphate protected as a methyl phosphotriester was obtained. This building block was used in the preparation of two 14-mer oligonucleotides with a central artificial bend due to the cyclic dinucleotide moiety. These were found to destabilise duplexes, slightly destabilise bulged duplexes but, to some extent, stabilise a three-way junction in high Mg(2+)-concentrations.
Nucleosides, Nucleotides and Nucleic Acids, 2007
A 3&a... more A 3'-C-branched LNA-type bicyclic nucleoside, containing a furanose ring locked in an N-type conformation, was synthesized from a known 3-C-vinyl allofuranose derivative using a strategy relying on the condensation with the nucleobase after the introduction of the branching hydroxymethyl chain by our recently developed RuO4 based protocol. This branched LNA nucleoside has a potential as a monomer for the functionalization of LNA.
Journal of Molecular Modeling, 2008
Aspartyl beta-semialdehyde dehydrogenase (ASADH) is an important enzyme, occupying the first bran... more Aspartyl beta-semialdehyde dehydrogenase (ASADH) is an important enzyme, occupying the first branch position of the biosynthetic pathway of the aspartate family of amino acids in bacteria, fungi and higher plants. It catalyses reversible dephosphorylation of L: -beta-aspartyl phosphate (betaAP) to L: -aspartate-beta-semialdehyde (ASA), a key intermediate in the biosynthesis of diaminopimelic acid (DAP)-an essential component of cross linkages in bacterial cell walls. Since the aspartate pathway is unique to plants and bacteria, and ASADH is the key enzyme in this pathway, it becomes an attractive target for antimicrobial agent development. Therefore, with the objective of deducing comparative structural models, we have described a molecular model emphasizing the uniqueness of ASADH from Mycobacterium tuberculosis (H37Rv) that should generate insights into the structural distinctiveness of this protein as compared to structurally resolved ASADH from other bacterial species. We find that mtASADH exhibits structural features common to bacterial ASADH, while other structural motifs are not present. Structural analysis of various domains in mtASADH reveals structural conservation among all bacterial ASADH proteins. The results suggest that the probable mechanism of action of the mtASADH enzyme might be same as that of other bacterial ASADH. Analysis of the structure of mtASADH will shed light on its mechanism of action and may help in designing suitable antagonists against this enzyme that could control the growth of Mycobacterium tuberculosis.
Journal of Chemical Research, 1997