Publications by authors named "Anil Mathur"

15 Publications

  • Page 1 of 1

Reduced Expression of Cerebral Metabotropic Glutamate Receptor Subtype 5 in Men with Fragile X Syndrome.

Brain Sci 2020 Nov 24;10(12). Epub 2020 Nov 24.

Department of Psychiatry and Behavioral Sciences-Child Psychiatry, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.

Glutamatergic receptor expression is mostly unknown in adults with fragile X syndrome (FXS). Favorable behavioral effects of negative allosteric modulators (NAMs) of the metabotropic glutamate receptor subtype 5 (mGluR) in knockout (KO) mouse models have not been confirmed in humans with FXS. Measurement of cerebral mGluR expression in humans with FXS exposed to NAMs might help in that effort. We used positron emission tomography (PET) to measure the mGluR density as a proxy of mGluR expression in cortical and subcortical brain regions to confirm target engagement of NAMs for mGluRs. The density and the distribution of mGluR were measured in two independent samples of men with FXS ( = 9) and typical development (TD) ( = 8). We showed the feasibility of this complex study including MRI and PET, meaning that this challenging protocol can be accomplished in men with FXS with an adequate preparation. Analysis of variance of estimated mGluR expression showed that mGluR expression was significantly reduced in cortical and subcortical regions of men with FXS in contrast to age-matched men with TD.
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http://dx.doi.org/10.3390/brainsci10120899DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7760509PMC
November 2020

Dataset of quantitative structured office measurements of movements in the extremities.

Data Brief 2020 Aug 18;31:105876. Epub 2020 Jun 18.

Section of High Resolution Brain Positron Emission Tomography Imaging, Division of Nuclear Medicine and Molecular Imaging, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, United States.

A low-cost quantitative structured office measurement of movements in the extremities of people with Parkinson's disease [1,2] was performed on people with Parkinson's disease, multiple system atrophy, and age-matched healthy volunteers. Participants underwent twelve videotaped procedures rated by a trained examiner while connected to four accelerometers [1,2] generating a trace of the three location dimensions expressed as spreadsheets [3,4]. The signals of the five repetitive motion items [1,2] underwent processing to fast Fourier [5] and continuous wavelet transforms [6]. The dataset [7] includes the coding form with scores of the live ratings [1,2], the raw files [3], the converted spreadsheets [4], and the fast Fourier [5] and continuous wavelet transforms [6]. All files are unfiltered. The data also provide findings suitable to compare and contrast with data obtained by investigators applying the same procedure to other populations. Since this is an inexpensive procedure to quantitatively measure motions in Parkinson's disease and other movement disorders, this will be a valuable resource to colleagues, particularly in underdeveloped regions with limited budgets. The dataset will serve as a template for other investigations to develop novel techniques to facilitate the diagnosis, monitoring, and treatment of Parkinson's disease, other movement disorders, and other nervous and mental conditions. The procedure will provide the basis to obtain objective quantitative measurements of participants in clinical trials of new agents.
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http://dx.doi.org/10.1016/j.dib.2020.105876DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7334383PMC
August 2020

Evaluation of F-RO-948 PET for Quantitative Assessment of Tau Accumulation in the Human Brain.

J Nucl Med 2018 12 10;59(12):1877-1884. Epub 2018 Aug 10.

Department of Radiology and Radiological Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland.

The availability of tau PET radioligands enables quantitative assessment of tau density and distribution in the human brain. We evaluated the kinetics of a novel radioligand, F-RO-948 (previously referred to as F-RO6958948), and its ability to identify tau positivity in individual patients with mild Alzheimer disease (AD). Eleven subjects with amyloid-positive mild AD, 5 amyloid-negative older control subjects (OC), and 5 younger control subjects (YC) completed 1 or 2 (4 AD and 5 OC) PET scans with F-RO-948 for 90, 120, or 200 min. The kinetics of the radioligand was evaluated with standard compartmental and noncompartmental models (with plasma data in 70% of cases), tissue-reference methods, and SUV ratio. These approaches were applied to assess the ability of F-RO-948 to discriminate AD subjects from OC subjects. The plasma reference graphical analysis appeared to be the optimal method of quantification for F-RO-948, yielding strictly time-consistent values of distribution volume and distribution volume ratio at 90 min against the analyses at 120 and 200 min. The reference tissue graphical analysis and SUV ratio were cross-validated against plasma reference graphical analysis. Test-retest evaluation showed excellent reproducibility. A proposed novel index of tau load, the regional tau-positive fraction, showed high values in the medial and lateral temporal and parietal regions in AD and successfully separated AD subjects from OC and YC subjects with a significant margin. F-RO-948 appears to be a promising radioligand for quantitative imaging of tau in the brain of AD patients.
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http://dx.doi.org/10.2967/jnumed.118.214437DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6278898PMC
December 2018

Characterization of 3 Novel Tau Radiopharmaceuticals, C-RO-963, C-RO-643, and F-RO-948, in Healthy Controls and in Alzheimer Subjects.

J Nucl Med 2018 12 4;59(12):1869-1876. Epub 2018 May 4.

Pharma Research and Early Development, Hoffmann-La Roche, Basel, Switzerland.

C-RO-963, C-RO-643, and F-RO-948 (previously referred to as C-RO6924963, C-RO6931643, and F-RO6958948, respectively) have been reported as promising PET tracers for tau imaging based on in vitro and preclinical PET data. Here we describe the first, to our knowledge, human evaluation of these novel radiotracers. Amyloid PET-positive Alzheimer disease (AD) subjects and younger controls each received 2 different tau tracers. Dynamic 90-min scans were obtained after bolus injection of C-RO-963, C-RO-643, or F-RO-948. Arterial blood sampling was performed on 11 healthy controls and 11 AD subjects. Regions were defined on MR images, and PET data were quantified by plasma reference graphical analysis (for total distribution volume) and target cerebellum ratio (SUV ratios of 60- to 90-min frames). SUV ratio images were also analyzed voxelwise. Five older controls each underwent 2 scans with F-RO-948 for evaluation of test-retest variability. Four AD subjects underwent a repeated F-RO-948 scan 6-22 mo after the first scan. Six additional healthy controls (3 men and 3 women; age range, 41-67 y) each underwent 1 whole-body dosimetry scan with F-RO-948. In younger controls, SUV was observed in the temporal lobe with values of approximately 3.0 for C-RO-963, 1.5 for C-RO-643, and 3.5 for F-RO-948. Over all brain regions and subjects, the trend was for F-RO-948 to have the highest SUV, followed by C-RO-963 and then C-RO-643. Regional analysis of SUV ratio and total distribution volume for C-RO-643 and F-RO-948 clearly discriminated the AD group from the healthy control groups. Compartmental modeling confirmed that C-RO-643 had lower brain entry than either C-RO-963 or F-RO-948 and that F-RO-948 showed better contrast between (predicted) areas of high versus low tau accumulation. Thus, our subsequent analysis focused on F-RO-948. Both voxelwise and region-based analysis of F-RO-948 binding in healthy controls versus AD subjects revealed multiple areas where AD subjects significantly differed from healthy controls. Of 22 high-binding regions, 13 showed a significant group difference (after ANOVA, = 45, < 10). Voxelwise analysis also revealed a set of symmetric clusters where AD subjects had higher binding than healthy controls (threshold of < 0.001, cluster size > 50). F-RO-948 demonstrates characteristics superior to C-RO-643 and C-RO-963 for characterization of tau pathology in AD. Regional binding data and kinetic properties of F-RO-948 compare favorably with other existing tau PET tracers.
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http://dx.doi.org/10.2967/jnumed.118.209916DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6278896PMC
December 2018

Metabotropic glutamate receptor 5 tracer [F]-FPEB displays increased binding potential in postcentral gyrus and cerebellum of male individuals with autism: a pilot PET study.

Cerebellum Ataxias 2018 12;5. Epub 2018 Feb 12.

1Department of Psychiatry, Division of Neuroscience Research, University of Minnesota Medical School, 420 Delaware St SE, MMC 392, Minneapolis, MN 55455 USA.

Background: Autism is a neurodevelopmental disorder that is first manifested during early childhood. Postmortem experiments have identified significantly elevated expression of metabotropic glutamate receptor 5 (mGluR5) in cerebellar vermis and prefrontal cortex of individuals with autism.

Methods: In the current study we employed the mGluR5 tracer [F]-3-fluoro-5-[(pyridin-3-yl)ethynyl]benzonitrile ([F]-FPEB) to quantify mGluR5 binding in vivo in adults with autism vs. healthy controls using positron emission tomography (PET).

Results: We identified significantly higher [F]-FPEB binding potential in the postcentral gyrus and cerebellum of individuals with autism. There was a significant negative correlation between age and [F]-FPEB binding potential in the cerebellum but not in the postcentral gyrus. In the precuneus, [F]-FPEB binding potential correlated positively with the lethargy subscale score for the Aberrant Behavioral Checklist (ABC). In cerebellum, there were significant negative correlations between [F]-FPEB binding potential and ABC total score, ABC hyperactivity subscale score, and the ABC inappropriate speech subscale score.

Conclusions: These novel findings demonstrate for the first time that mGluR5 binding is altered in critical brain areas of subjects with autism, suggesting abnormal glutamate signaling in these regions. Finally, the correlations between altered [F]-FPEB binding potential in the cerebellum and precuneus suggest that some autistic symptoms may be influenced by abnormal glutamate signaling.
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http://dx.doi.org/10.1186/s40673-018-0082-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5810020PMC
February 2018

Objectively Measured Sleep and β-amyloid Burden in Older Adults: A Pilot Study.

SAGE Open Med 2014 Aug;2

Department of Neurology, Johns Hopkins School of Medicine, Baltimore, MD ; Department of Neuroscience, Johns Hopkins School of Medicine, Baltimore, MD.

Background/aims: Although disturbed sleep is associated with cognitive deficits, the association between sleep disturbance and Alzheimer's disease (AD) pathology is unclear. In this pilot study, we examined the extent to which sleep duration, sleep quality, and sleep-disordered breathing (SDB) are associated with β-amyloid (Aβ) deposition in the brains of living humans.

Methods: We studied 13 older adults (8 with normal cognition and 5 with mild cognitive impairment (MCI)). Participants completed neuropsychological testing, polysomnography and Aβ imaging with [C]-Pittsburgh compound B.

Results: Among participants with MCI, higher apnea-hypopnea index and oxygen desaturation index were associated with greater Aβ deposition, globally and regionally in the precuneus. There were no significant associations between SDB and Aβ deposition among cognitively normal participants. There were no significant associations between sleep duration or sleep fragmentation and Aβ deposition.

Conclusion: These preliminary results suggest that, among older adults with MCI, greater SDB severity is associated with greater Aβ deposition.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4304392PMC
http://dx.doi.org/10.1177/2050312114546520DOI Listing
August 2014

PET imaging of high-affinity α4β2 nicotinic acetylcholine receptors in humans with 18F-AZAN, a radioligand with optimal brain kinetics.

J Nucl Med 2013 Aug 25;54(8):1308-14. Epub 2013 Jun 25.

Department of Radiology, School of Medicine, Johns Hopkins University, Baltimore, Maryland, USA.

Unlabelled: We evaluated (-)-2-(6-[(18)F]fluoro-2,3'-bipyridin-5'-yl)-7-methyl-7-aza-bicyclo[2.2.1]heptane ((18)F-AZAN), a novel radiotracer that binds to α4β2 nicotinic acetylcholine receptors (α4β2-nAChRs) and shows high specific binding and rapid and reversible kinetics in the baboon and human brain.

Methods: We tested safety tolerability and test-retest reliability (n = 5) and proposed initial quantification of (18)F-AZAN receptors in 3 healthy human subjects who had nicotine exposure and 9 who did not. We also present a receptor blocking study in a nicotine subject dosed with the α4β2-nAChR-selective partial agonist varenicline.

Results: Radiation dosimetry PET/CT experiments indicated that most human organs received doses between 0.008 and 0.015 mSv/MBq, with an effective dose of approximately 0.014 mSv/MBq. The tracer rapidly entered the brain, and the peak was reached before 20 min, even for thalamus. Ninety-minute scans were sufficient for (18)F-AZAN to obtain the ratio at equilibrium of specifically bound radioligand to nondisplaceable radioligand in tissue (BPND) using plasma reference graphical analysis, which showed excellent reproducibility of BPND (test-retest variability < 10%) in the nAChR-rich brain regions. Regional plasma reference graphical analysis BP(ND) values exceeded 2 in the midbrain tegmental nuclei, lateral geniculate body, and thalamus for nonsmokers (n = 9) but were less than 1 in the nAChR-poor brain regions. There was a dramatic reduction of (18)F-AZAN brain uptake in smokers and varenicline-treated subjects.

Conclusion: (18)F-AZAN is a highly specific, safe, and effective PET radioligand for human subjects that requires only 90 min of PET scanning to estimate high-affinity α4β2-nAChR in the living human brain.
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http://dx.doi.org/10.2967/jnumed.112.108001DOI Listing
August 2013

Biological treatment and modeling aspect of BTEX abatement process in a biofilter.

Bioresour Technol 2013 Aug 13;142:9-17. Epub 2013 May 13.

Chemical Engineering Department, Indian Institute of Technology, Roorkee 247667, India.

In the present work, a laboratory scale corn-cob based biofilter inoculated with Bacillus sphaericus (MTCC 8103) was used for degradation of BTEX for a period of 86 days. The overall performance of a biofilter evaluated in terms of its elimination capacity by using 3-D mesh technique. Maximum removal efficiency was found more than 96.43% for all four compounds in each phase of experiments. A maximum elimination capacity (EC) of 60.89 gm(-3)h(-1) of the biofilter was obtained at inlet BTEX load of 63.14 gm(-3)h(-1). The follow-up of carbon dioxide concentration profile through the biofilter revealed that the mass ratio of carbon dioxide produced to the BTEX removed was approximately 2.2, which confirms complete degradation of BTEX. Moreover, BTEX concentration profile along the biofilter depth bed also determined by convection-diffusion reactor (CDR) model.
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http://dx.doi.org/10.1016/j.biortech.2013.05.005DOI Listing
August 2013

Performance evaluation and model analysis of BTEX contaminated air in corn-cob biofilter system.

Bioresour Technol 2013 Apr 27;133:166-74. Epub 2013 Jan 27.

Chemical Engineering Department, Indian Institute of Technology, Roorkee, India.

Biofiltration of BTEX with corn-cob packing material have been performed for a period of 68 days in five distinct phases. The overall performance of a biofilter has been evaluated in terms of its elimination capacity by using 3-D mesh techniques. Maximum removal efficiency was found more than 99.85% of all four compounds at an EBRT of 3.06 min in phase I for an inlet BTEX concentration of 0.0970, 0.0978, 0.0971 and 0.0968 g m(-3), respectively. Nearly 100% removal achieved at average BTEX loadings of 20.257 g m(-3) h(-1) to biofilter. A maximum elimination capacity (EC) of 20.239 g m(-3) h(-1) of the biofilter was obtained at inlet BTEX load of 20.391 g m(-3) h(-1). Moreover, using convection-diffusion reaction (CDR) model for biofilter depth shows good agreement with the experimental values for benzene, toluene and ethyl benzene, but for o-xylene the model results deviated from the experimental.
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http://dx.doi.org/10.1016/j.biortech.2013.01.087DOI Listing
April 2013

Modelling and computational fluid dynamic behaviour of a biofilter treating benzene.

Bioresour Technol 2012 Dec 7;125:200-7. Epub 2012 Sep 7.

Chemical Engineering Department, Indian Institute of Technology, Roorkee 247667, India.

Biofiltration of an air stream containing benzene has been studied in a laboratory biofilter packed with a mixture of compost, sugar cane bagasse and GAC. In this study, the overall performance of a biofilter has been evaluated in terms of its elimination capacity by using 3-D mesh techniques. The overall results indicate that the agreement between experimental data and estimated model predictions is excellent for benzene. The benzene concentration profiles along the depth of biofilter have also been determined using a convection-diffusion reactor (CDR) model and computational fluid dynamic (CFD) technique. At low flow rates and low concentrations of benzene, the concentration profile throughout the biofilter shows good agreement with CDR model and it becomes more curved and resembles typical decay. Combined analysis of experimental results with CDR model and the CFD shows that the profile of benzene at low concentration becomes more curved and then linear at high concentration. The benzene profiles obtained by CFD are within 5% accuracy of experimental results. The CDR and CFD models are found to be able to predict concentration profiles preciously with depth under the experimental conditions.
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http://dx.doi.org/10.1016/j.biortech.2012.08.134DOI Listing
December 2012

Biodegradation of mono-chlorobenzene by using a trickle bed air biofilter (TBAB).

J Environ Biol 2010 Jul;31(4):445-51

Applied Mechanics Department, Motilal Nehru National Institute of Technology, Allahabad - 211 004, India.

In the present study, performance of the trickle bed airbiofilter (TBAB) for treating mono-chlorobenzene (MCB) was evaluated for various influent volatile organic compound (VOC) loadings using coal and mixed consortium of activated sludge as the packing material. Microbial acclimation to MCB was achieved by exposing the system continuously for 31 d to an average inlet MCB concentration of 0.688 g m(-3) at an empty bed residence time (EBRT) of 188 s. The TBAB achieved maximum removal efficiency of 87% at an EBRT of 188 s for an inlet concentration of 0.681 g m(-3), which is quite significance than the values reported in the literature. Elimination capacities of MCB increased with an increase of the influent VOC loading, but an opposite trend was observed for the removal efficiency The maximum elimination capacity of the biofilter was 110.75 g m(-3) hr(-1) at an inlet MCB concentration of 1.47 g m(-3). The effect of starvation on the TBAB was also studied. After starvation, the TBAB lost its ability to degrade MCB initially However the biofilter recovered very quickly Evaluation of the concentration profile along the bed height indicated that the bottom section of TBAB has the best performance for all concentrations. By using Wani's method of macrokinetic determination based on simple Monod kinetics, the maximum removal rate of MCB, r(max) and saturation constant K(m) was to be found as 1.304 g m(-3)s(-1) and 113.446 g m(-3), respectively.
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July 2010

Biodegradation of pyridine by the new bacterial isolates S. putrefaciens and B. sphaericus.

J Hazard Mater 2008 Sep 15;157(2-3):335-43. Epub 2008 Jan 15.

Biotechnology Department, Motilal Nehru National Institute of Technology, Allahabad, India.

In this study, two bacterial strains capable of utilizing pyridine as a sole carbon source were isolated from biofilters. Based on the biochemical test, the organisms were identified as Shewanella putrefaciens and Bacillus sphaericus. In liquid cultures, S. putrefaciens and B. sphaericus degraded pyridine quite effectively up to 500 mg L(-1). S. putrefaciens degrades 500 mg L(-1) of pyridine completely within 140 h, whereas the B. sphaericus degrades 500 mg L(-1) of pyridine only nearly 75% and takes a longer duration of 150 h. S. putrefaciens used pyridine as sole carbon and energy source better than B. sphaericus. Monod's and Haldane's inhibitory growth models were used to obtain maximum specific growth rate (micro(max)), half saturation (K(s)) and substrate inhibition (K(i)) constant for pyridine by using S. putrefaciens and B. sphaericus. The high value of K(i) for S. putrefaciens than B. sphaericus indicates that the inhibition effect can be observed only in a high concentration range. The S. putrefaciens degrades pyridine with a faster rate than B. sphaericus. S. putrefaciens can be used effectively for the treatment of pyridine bearing wastewater and as an inoculum in a biofilter treating pyridine-laden gas.
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http://dx.doi.org/10.1016/j.jhazmat.2007.12.112DOI Listing
September 2008

Biofiltration and kinetic aspects of a biotrickling filter for the removal of paint solvent mixture laden air stream.

J Hazard Mater 2008 Apr 7;152(3):1027-36. Epub 2007 Aug 7.

Chemical Engineering Department, Indian Institute of Technology, Roorkee 247667, India.

In the present study, removal of methyl ethyl ketone (MEK), toluene, n-butyl acetate and o-xylene (MTBX) emitted from the paint industry was carried out in a coal based biotrickling filter. When the influent MTBX loadings were less than 120 gm(-3)h(-1), nearly 100% removal could be achieved. A maximum elimination capacity of 184.86 gm(-3)h(-1) was obtained at a MTBX load of 278.27 gm(-3)h(-1) with an empty bed residence time of 42.4s in phase V. Results showed that the condition was the most favorable for n-butyl acetate degradation followed by MEK, toluene and then o-xylene. The corresponding maximum removal rate, r(max) values of MTBX were calculated as 0.085, 0.033, 0.16 and 0.024 gm(-3)h(-1), respectively. Standard deviation of error in prediction of MEK, toluene and o-xylene removal were within limit of 10%, while in the case of n-butyl acetate this was approximately 60%. The MTBX concentration profiles along the depth were also determined by using convection-diffusion reaction (CDR) model. It was observed that at low concentration and low flow rate, the model is in good agreement with the experimental values for MEK, toluene and n-butyl acetate, but for o-xylene the model results deviated from the experimental.
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http://dx.doi.org/10.1016/j.jhazmat.2007.07.112DOI Listing
April 2008

Combined removal of BTEX in air stream by using mixture of sugar cane bagasse, compost and GAC as biofilter media.

J Hazard Mater 2007 Sep 15;148(1-2):64-74. Epub 2007 Feb 15.

Chemical Engineering Department, Indian Institute of Technology Roorkee, Roorkee 247667, India.

Biofiltration of air stream containing mixture of benzene, toluene, ethyl benzene and o-xylene (BTEX) has been studied in a lab-scale biofilter packed with a mixture of compost, sugar cane bagasse and granulated activated carbon (GAC) in the ratio 55:30:15 by weight. Microbial acclimation was achieved in 30 days by exposing the system to average BTEX inlet concentration of 0.4194 gm(-3) at an empty bed residence time (EBRT) of 2.3 min. Biofilter achieved maximum removal efficiency more than 99% of all four compounds for throughout its operation at an EBRT of 2.3 min for an inlet concentration of 0.681 gm(-3), which is quite significance than the values reported in the literature. The results indicate that when the influent BTEX loadings were less than 68 gm(-3)h(-1) in the biofilter, nearly 100% removal could be achieved. A maximum elimination capacity (EC) of 83.65 gm(-3)h(-1) of the biofilter was obtained at inlet BTEX load of 126.5 gm(-3)h(-1) in phase IV. Elimination capacities of BTEX increased with the increase in influent VOC loading, but an opposite trend was observed for the removal efficiency. The production of CO(2) in each phase (gm(-3)h(-1)) was also observed at steady state (i.e. at maximum removal efficiency). Moreover, the high concentrations of nitrogen in the nutrient solution may adversely affect the microbial activity possibly due to the presence of high salt concentrations. Furthermore, an attempt was also made to isolate the most profusely grown BTEX-degrading strain. A Gram-positive strain had a high BTEX-degrading activity and was identified as Bacillus sphaericus by taxonomical analysis, biochemical tests and 16S rDNA gene analysis methods.
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http://dx.doi.org/10.1016/j.jhazmat.2007.02.030DOI Listing
September 2007

Kinetics of the removal of mono-chlorobenzene vapour from waste gases using a trickle bed air biofilter.

J Hazard Mater 2006 Oct 29;137(3):1560-8. Epub 2006 Apr 29.

Department of Chemical Engineering, Indian Institute of Technology Roorkee, Roorkee-247667, Uttaranchal, India.

The performance of a trickle bed air biofilter (TBAB) in the removal of mono-chlorobenzene (MCB) was evaluated in concentrations varying from 0.133 to 7.187 g m(-3) and at empty bed residence time (EBRT) varying from 37.7 to 188.52 s. More than 90% removal efficiency in the trickle bed air biofilter was achieved for the inlet MCB concentration up to 1.069 g m(-3) and EBRT less than 94.26 s. The trickle bed air biofilter was constructed with coal packing material, inoculated with a mixed consortium of activated sludge obtained from sewage treatment plant. The continuous performance of the removal of MCB in the trickle bed air biofilter was monitored for various gas concentrations, gas flow rates, and empty bed residence time. The experiment was conducted for a period of 75 days. The trickle bed air biofilter degrading MCB with an average elimination capacity of 80 g m(-3) h(-1) was obtained. The effect of starvation was also studied. After starvation period of 8 days, the degradation was low but recovered within a short period of time. Using macrokinetic determination method, the Michaelis-Menten kinetic constant K(m) and maximum reaction rate, r(max) evaluated as 0.121 g m(-3) s(-1) and 7.45 g m(-3), respectively.
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http://dx.doi.org/10.1016/j.jhazmat.2006.04.042DOI Listing
October 2006