Summary We studied the transport and transformation of urea under steady-state conditions in two ... more Summary We studied the transport and transformation of urea under steady-state conditions in two soils and at three water salinities (1.0, 5.0, and 10.0 dS/m) using laboratory soil columns. A mathematical model that considers diffusion, convection, adsorption and first-order kinetic transformation of nitrogen was used to describe measured effluent concentration of the two nitrogen species. Increasing salt levels in the
... Indian Institute of Technology Bombay, Powai, Mumbai 400076, India S. Lakshmi, PK Joshi, and ... more ... Indian Institute of Technology Bombay, Powai, Mumbai 400076, India S. Lakshmi, PK Joshi, and HC ... pragya@phy.iitb.ac.in 054302-1 The ï¬ rst lifetime measurement was performed at ... band was observed [6]. V. CONCLUSION The authors would like to thank Dr. I. Ragnarsson ...
... PHYSICAL REVIEW C 81, 054322 (2010) High spin spectroscopy and shears mechanism in 107 In D. ... more ... PHYSICAL REVIEW C 81, 054322 (2010) High spin spectroscopy and shears mechanism in 107 In D. Negi,1,* T. Trivedi,2 A. Dhal,1,8 S. Kumar,3 V. Kumar,3 S. Roy,4 MK Raju,5 S. Appannababu,6 G. Mohanto,1 J. Kaur,7 RK Sinha,8 R. Kumar,1 RP ... S. Sihotra, Z. Naik, R. Palit ...
Little is known about survival on peritoneal dialysis (PD) in Indian patients since the initiatio... more Little is known about survival on peritoneal dialysis (PD) in Indian patients since the initiation of continuous ambulatory PD (CAPD) in India in 1991. Survival data from single centers with small numbers have been published. A retrospective 4-center analysis for predictors of survival >3 years in south Indian chronic PD patients. A total of 309 patients were trained during the observation period (from 1999 to 2004) and were analyzed in a multicenter study (4 centers), including 150 patients (male:female 109:41) that survived…
Patients with autoimmune thyroiditis can present with thyroid function that varies from euthyroid... more Patients with autoimmune thyroiditis can present with thyroid function that varies from euthyroidism to frank hypothyroidism or occasionally hyperthyroidism. Although there is a risk of progression from the euthyroid or subclinical hypothyroid state to frank hypothyroidism, the rate of progression is not known. Subjects with diffuse goiter and autoimmune thyroiditis were followed up to observe the rate of deterioration in thyroid function from euthyroid and subclinical hypothyroid states to hypothyroidism. Patients who presented with goiter and autoimmune thyroiditis were grouped as those with euthyroidism, subclinical hypothyroidism, and overt hypothyroidism on the basis of levels of thyroxine and thyrotropin at presentation. Patients were followed up for a minimum duration of 24 months with periodic monitoring of thyroid function. Ninety-eight consecutive subjects (aged of 8-18 years) with a diagnosis of autoimmune thyroiditis and diffuse goiter were studied. At presentation, in 24 subjects (24.5%) thyroid function was normal (euthyroidism), 32 (32.6%) had subclinical hypothyroidism, and the remaining 42 subjects (42.9%) had hypothyroidism. All of the subjects with hypothyroid were maintained euthyroid on thyroxine during follow-up. Hypothyroidism developed in 3 of 24 patients with euthyroidism and in 4 of 32 patients with subclinical hypothyroidism. Subjects with goitrous autoimmune thyroiditis need periodic monitoring of thyroid function. Development of thyroid dysfunction is insidious and may not be accompanied by symptoms and clinical signs. In pediatric and adolescent age groups it is imperative to correct thyroid dysfunction to achieve optimal growth and development.
The extensive use of silver nanoparticles needs a synthesis process that is greener without compr... more The extensive use of silver nanoparticles needs a synthesis process that is greener without compromising their properties. The present study describes a novel green synthesis of silver nanoparticles using Guava (Psidium guajava) leaf extract. In order to compare with the conventionally synthesized ones, we also prepared Ag-NPs by chemical reduction. Their optical and morphological characteristics were thoroughly investigated and tested for their antibacterial properties on Escherichia coli. The green synthesized silver nanoparticles showed better antibacterial properties than their chemical counterparts even though there was not much difference between their morphologies. Fourier transform infrared (FTIR) spectroscopic analysis of the used extract and as-synthesized silver nanoparticles suggests the possible reduction of Ag(+) by the water-soluble ingredients of the guava leaf like tannins, eugenol and flavonoids. The possible reaction mechanism for the reduction of Ag(+) has been proposed and discussed. The time-dependent electron micrographs and the simulation studies indicated that a physical interaction between the silver nanoparticles and the bacterial cell membrane may be responsible for this effect. Based on the findings, it seems very reasonable to believe that this greener way of synthesizing silver nanoparticles is not just an environmentally viable technique but it also opens up scope to improve their antibacterial properties.
Mutation Research/Genetic Toxicology and Environmental Mutagenesis, 2009
Methylphenidate (MPH, Ritalin), has been prescribed to treat attention deficit/hyperactivity diso... more Methylphenidate (MPH, Ritalin), has been prescribed to treat attention deficit/hyperactivity disorder (ADHD) since its approval by the FDA over 50 years ago. Diagnoses of pediatric patients with ADHD and the administration of MPH to treat the symptoms have increased in prevalence in recent years. A 2005 study by El-Zein et al. reported statistically significant increases in cytogenetic anomalies including chromosomal aberrations (CA), micronuclei (MN) and sister chromatid exchanges (SCEs) in peripheral blood lymphocytes cultured from pediatric patients treated for 3 months with MPH. These findings led to wide-spread concern regarding the potential for genotoxic risks associated with prolonged administration of MPH. The study described in the present paper was designed to repeat the El-Zein effort with a much larger sample size. The subjects (N = 109) were randomized into two groups: one treated with MPH as well as behavior therapy, the other was a control group that received behavior therapy only. We evaluated CAs, MN, and SCEs in peripheral blood lymphocytes in samples obtained prior to therapy and after 3 months of treatment with MPH. The data were analyzed using a Poisson regression model with a generalized estimating equation method adjusted for several covariates including time, treatment-by-time interaction, sex, and age group. The log(e) rate ratios of the MPH plus behavior therapy and behavior therapy groups were compared. The frequencies of CAs, MN, and SCEs were not increased in the MPH plus behavior therapy group when compared to the behavior therapy group only (p = 0.53, 0.28, 0.81, respectively). These results provide evidence in a large cohort that MPH does not induce cytogenetic anomalies in children, in contrast to the findings of the El-Zein study.
A genomic library from an S29/S29 self-incompatible genotype of Brassica oleracea was screened wi... more A genomic library from an S29/S29 self-incompatible genotype of Brassica oleracea was screened with a probe carrying part of the catalytic domain of a Brassica S-receptor kinase (SRK)-like gene. Six positive phage clones with varying hybridisation intensities (K1 to K6) were purified and characterised. A 650-700 bp region corresponding to the probe was excised from each clone and sequenced. DNA and predicted protein sequence comparisons based on a multiple alignment identified K5 as a pseudogene, whereas the others could encode functional proteins. K3 was found to have lost an intron from its genomic sequence. The six genes display different degrees of sequence similarity and form two distinct clusters in a dendrogram. The 98% similarity between K4 and K6, which extends across intron sequences, suggests that these might be very recently diverged alleles or daughters of a duplication. In addition, K2 showed a comparably high similarity to the probe. Clones K1, K3 and K5 cross-hybridised with an SLG29 cDNA probe, indicating the presence of upstream receptor domains homologous to the Brassica SLG gene. This suggests that the previously reported S sequence complexity may be ascribed to a large receptor kinase gene family.
The ceramic system La 0.7 Ca 0.3 MnO 3 was prepared by solid state method and impedance measureme... more The ceramic system La 0.7 Ca 0.3 MnO 3 was prepared by solid state method and impedance measurements were carried out as a function of frequency (100 Hz 1 MHz) in the temperature range 303529 K. An equivalent circuit model that represented the data well was arrived ...
The manuscript describes a study on the blood cholinesterase (ChE) level in an exposed population... more The manuscript describes a study on the blood cholinesterase (ChE) level in an exposed population at different interval of time after spraying with malathion suspension (SRES) use for kala-azar vector control in an endemic area of Bihar, India. The toxicity of a 5% malathion formulation in the form of a slow release emulsified suspension (SRES) was assessed by measuring serum ChE levels in spraymen and in the exposed population. The study showed a significant decrease in ChE levels in the spraymen (p < 0.01) after one week of spraying and in exposed population one week and one month after of spraying (p < 0.01), but was still within the normal range of ChE concentration, one year after spraying, the ChE concentration in the exposed population was the same as prior to spraying (p > 0.01). On no occasion was the decrease in ChE level alarming. A parallel examination of the clinical status also showed the absence of any over toxicity or any behavioural changes in the exposed population. Hence, it may be concluded that 5% malathion slow release formulation, SRES, is a safe insecticide for use as a vector control measure in endemic areas of kala-azar in Bihar, India so long as good personal protection for spraymen is provided to minimize absorption and it can substitute the presently used traditional DDT spray.
... Effect of Gd 3+ substitution on dielectric properties of nano cobalt ferrite. Anu Rana a , lo... more ... Effect of Gd 3+ substitution on dielectric properties of nano cobalt ferrite. Anu Rana a , low asterisk , E-mail The Corresponding Author , OP Thakur a and Vinod Kumar b. ... [4] AV Ramana Reddy, G. Ranga Mphan, D. Ravinder and BS Boyanov, J Mat Sci 34 (1999), p. 3169. ...
This investigation attempts to identify the mechanism (s) involved in the fat deposition in a pho... more This investigation attempts to identify the mechanism (s) involved in the fat deposition in a photoperiodic migratory species, the Blackheaded bunting (Emberiza melanocephala). Groups of photosensitive male buntings were exposed to resonance, interrupted night, ...
Summary We studied the transport and transformation of urea under steady-state conditions in two ... more Summary We studied the transport and transformation of urea under steady-state conditions in two soils and at three water salinities (1.0, 5.0, and 10.0 dS/m) using laboratory soil columns. A mathematical model that considers diffusion, convection, adsorption and first-order kinetic transformation of nitrogen was used to describe measured effluent concentration of the two nitrogen species. Increasing salt levels in the
... Indian Institute of Technology Bombay, Powai, Mumbai 400076, India S. Lakshmi, PK Joshi, and ... more ... Indian Institute of Technology Bombay, Powai, Mumbai 400076, India S. Lakshmi, PK Joshi, and HC ... pragya@phy.iitb.ac.in 054302-1 The ï¬ rst lifetime measurement was performed at ... band was observed [6]. V. CONCLUSION The authors would like to thank Dr. I. Ragnarsson ...
... PHYSICAL REVIEW C 81, 054322 (2010) High spin spectroscopy and shears mechanism in 107 In D. ... more ... PHYSICAL REVIEW C 81, 054322 (2010) High spin spectroscopy and shears mechanism in 107 In D. Negi,1,* T. Trivedi,2 A. Dhal,1,8 S. Kumar,3 V. Kumar,3 S. Roy,4 MK Raju,5 S. Appannababu,6 G. Mohanto,1 J. Kaur,7 RK Sinha,8 R. Kumar,1 RP ... S. Sihotra, Z. Naik, R. Palit ...
Little is known about survival on peritoneal dialysis (PD) in Indian patients since the initiatio... more Little is known about survival on peritoneal dialysis (PD) in Indian patients since the initiation of continuous ambulatory PD (CAPD) in India in 1991. Survival data from single centers with small numbers have been published. A retrospective 4-center analysis for predictors of survival >3 years in south Indian chronic PD patients. A total of 309 patients were trained during the observation period (from 1999 to 2004) and were analyzed in a multicenter study (4 centers), including 150 patients (male:female 109:41) that survived…
Patients with autoimmune thyroiditis can present with thyroid function that varies from euthyroid... more Patients with autoimmune thyroiditis can present with thyroid function that varies from euthyroidism to frank hypothyroidism or occasionally hyperthyroidism. Although there is a risk of progression from the euthyroid or subclinical hypothyroid state to frank hypothyroidism, the rate of progression is not known. Subjects with diffuse goiter and autoimmune thyroiditis were followed up to observe the rate of deterioration in thyroid function from euthyroid and subclinical hypothyroid states to hypothyroidism. Patients who presented with goiter and autoimmune thyroiditis were grouped as those with euthyroidism, subclinical hypothyroidism, and overt hypothyroidism on the basis of levels of thyroxine and thyrotropin at presentation. Patients were followed up for a minimum duration of 24 months with periodic monitoring of thyroid function. Ninety-eight consecutive subjects (aged of 8-18 years) with a diagnosis of autoimmune thyroiditis and diffuse goiter were studied. At presentation, in 24 subjects (24.5%) thyroid function was normal (euthyroidism), 32 (32.6%) had subclinical hypothyroidism, and the remaining 42 subjects (42.9%) had hypothyroidism. All of the subjects with hypothyroid were maintained euthyroid on thyroxine during follow-up. Hypothyroidism developed in 3 of 24 patients with euthyroidism and in 4 of 32 patients with subclinical hypothyroidism. Subjects with goitrous autoimmune thyroiditis need periodic monitoring of thyroid function. Development of thyroid dysfunction is insidious and may not be accompanied by symptoms and clinical signs. In pediatric and adolescent age groups it is imperative to correct thyroid dysfunction to achieve optimal growth and development.
The extensive use of silver nanoparticles needs a synthesis process that is greener without compr... more The extensive use of silver nanoparticles needs a synthesis process that is greener without compromising their properties. The present study describes a novel green synthesis of silver nanoparticles using Guava (Psidium guajava) leaf extract. In order to compare with the conventionally synthesized ones, we also prepared Ag-NPs by chemical reduction. Their optical and morphological characteristics were thoroughly investigated and tested for their antibacterial properties on Escherichia coli. The green synthesized silver nanoparticles showed better antibacterial properties than their chemical counterparts even though there was not much difference between their morphologies. Fourier transform infrared (FTIR) spectroscopic analysis of the used extract and as-synthesized silver nanoparticles suggests the possible reduction of Ag(+) by the water-soluble ingredients of the guava leaf like tannins, eugenol and flavonoids. The possible reaction mechanism for the reduction of Ag(+) has been proposed and discussed. The time-dependent electron micrographs and the simulation studies indicated that a physical interaction between the silver nanoparticles and the bacterial cell membrane may be responsible for this effect. Based on the findings, it seems very reasonable to believe that this greener way of synthesizing silver nanoparticles is not just an environmentally viable technique but it also opens up scope to improve their antibacterial properties.
Mutation Research/Genetic Toxicology and Environmental Mutagenesis, 2009
Methylphenidate (MPH, Ritalin), has been prescribed to treat attention deficit/hyperactivity diso... more Methylphenidate (MPH, Ritalin), has been prescribed to treat attention deficit/hyperactivity disorder (ADHD) since its approval by the FDA over 50 years ago. Diagnoses of pediatric patients with ADHD and the administration of MPH to treat the symptoms have increased in prevalence in recent years. A 2005 study by El-Zein et al. reported statistically significant increases in cytogenetic anomalies including chromosomal aberrations (CA), micronuclei (MN) and sister chromatid exchanges (SCEs) in peripheral blood lymphocytes cultured from pediatric patients treated for 3 months with MPH. These findings led to wide-spread concern regarding the potential for genotoxic risks associated with prolonged administration of MPH. The study described in the present paper was designed to repeat the El-Zein effort with a much larger sample size. The subjects (N = 109) were randomized into two groups: one treated with MPH as well as behavior therapy, the other was a control group that received behavior therapy only. We evaluated CAs, MN, and SCEs in peripheral blood lymphocytes in samples obtained prior to therapy and after 3 months of treatment with MPH. The data were analyzed using a Poisson regression model with a generalized estimating equation method adjusted for several covariates including time, treatment-by-time interaction, sex, and age group. The log(e) rate ratios of the MPH plus behavior therapy and behavior therapy groups were compared. The frequencies of CAs, MN, and SCEs were not increased in the MPH plus behavior therapy group when compared to the behavior therapy group only (p = 0.53, 0.28, 0.81, respectively). These results provide evidence in a large cohort that MPH does not induce cytogenetic anomalies in children, in contrast to the findings of the El-Zein study.
A genomic library from an S29/S29 self-incompatible genotype of Brassica oleracea was screened wi... more A genomic library from an S29/S29 self-incompatible genotype of Brassica oleracea was screened with a probe carrying part of the catalytic domain of a Brassica S-receptor kinase (SRK)-like gene. Six positive phage clones with varying hybridisation intensities (K1 to K6) were purified and characterised. A 650-700 bp region corresponding to the probe was excised from each clone and sequenced. DNA and predicted protein sequence comparisons based on a multiple alignment identified K5 as a pseudogene, whereas the others could encode functional proteins. K3 was found to have lost an intron from its genomic sequence. The six genes display different degrees of sequence similarity and form two distinct clusters in a dendrogram. The 98% similarity between K4 and K6, which extends across intron sequences, suggests that these might be very recently diverged alleles or daughters of a duplication. In addition, K2 showed a comparably high similarity to the probe. Clones K1, K3 and K5 cross-hybridised with an SLG29 cDNA probe, indicating the presence of upstream receptor domains homologous to the Brassica SLG gene. This suggests that the previously reported S sequence complexity may be ascribed to a large receptor kinase gene family.
The ceramic system La 0.7 Ca 0.3 MnO 3 was prepared by solid state method and impedance measureme... more The ceramic system La 0.7 Ca 0.3 MnO 3 was prepared by solid state method and impedance measurements were carried out as a function of frequency (100 Hz 1 MHz) in the temperature range 303529 K. An equivalent circuit model that represented the data well was arrived ...
The manuscript describes a study on the blood cholinesterase (ChE) level in an exposed population... more The manuscript describes a study on the blood cholinesterase (ChE) level in an exposed population at different interval of time after spraying with malathion suspension (SRES) use for kala-azar vector control in an endemic area of Bihar, India. The toxicity of a 5% malathion formulation in the form of a slow release emulsified suspension (SRES) was assessed by measuring serum ChE levels in spraymen and in the exposed population. The study showed a significant decrease in ChE levels in the spraymen (p < 0.01) after one week of spraying and in exposed population one week and one month after of spraying (p < 0.01), but was still within the normal range of ChE concentration, one year after spraying, the ChE concentration in the exposed population was the same as prior to spraying (p > 0.01). On no occasion was the decrease in ChE level alarming. A parallel examination of the clinical status also showed the absence of any over toxicity or any behavioural changes in the exposed population. Hence, it may be concluded that 5% malathion slow release formulation, SRES, is a safe insecticide for use as a vector control measure in endemic areas of kala-azar in Bihar, India so long as good personal protection for spraymen is provided to minimize absorption and it can substitute the presently used traditional DDT spray.
... Effect of Gd 3+ substitution on dielectric properties of nano cobalt ferrite. Anu Rana a , lo... more ... Effect of Gd 3+ substitution on dielectric properties of nano cobalt ferrite. Anu Rana a , low asterisk , E-mail The Corresponding Author , OP Thakur a and Vinod Kumar b. ... [4] AV Ramana Reddy, G. Ranga Mphan, D. Ravinder and BS Boyanov, J Mat Sci 34 (1999), p. 3169. ...
This investigation attempts to identify the mechanism (s) involved in the fat deposition in a pho... more This investigation attempts to identify the mechanism (s) involved in the fat deposition in a photoperiodic migratory species, the Blackheaded bunting (Emberiza melanocephala). Groups of photosensitive male buntings were exposed to resonance, interrupted night, ...
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