Ramesh Babu - Academia.edu (original) (raw)

Papers by Ramesh Babu

Research paper thumbnail of Total synthesis of chamigrene and laurencenone C via Ireland ester Claisen rearrangement and an intramolecular type II carbonyl ene reaction sequence

Tetrahedron, 2008

A combination of Ireland ester Claisen rearrangement and intramolecular type II carbonyl ene reac... more A combination of Ireland ester Claisen rearrangement and intramolecular type II carbonyl ene reactions were exploited for the total synthesis of chamigrenes containing a quaternary carbon atom next to the spirocentre in spiro[5.5]undecane.

Research paper thumbnail of Effect of pH on the morphology, mechanical and optical properties of L-arginine monohydrobromide monohydrate (LAHBr) single crystals

Bulletin of Materials Science, Sep 1, 2015

Research paper thumbnail of Agro waste material as ecofriendly adsorbent for the removal of Zn(II): isotherm, kinetic, thermodynamic and optimization studies

DESALINATION AND WATER TREATMENT, 2019

Contamination of environment by heavy metals posed significant threat to human, animals and plant... more Contamination of environment by heavy metals posed significant threat to human, animals and plants health due their accumulation in the living tissues and their non-degradability. Excess of zinc in living system is detrimental to health adverse effects therefore; this work investigates the feasibility of removal of Zn 2+ from aqueous solution using agricultural biowaste adsorbent prepared from groundnut shell. Effects of some important parameters such as pH, initial metal concentrations, temperature and adsorbent dosage on adsorption process were investigated. These factors were optimized by Box-Behnken experimental design using Design Expert 6.0. The prepared biosorbent was characterized using Scanning electron microscopy (SEM), Fourier Transform Infrared (FT-IR) and X-ray dispersion (XRD). Data from kinetic study was analyzed with pseudo-first-order and pseudo-second-order kinetic models while equilibrium data were evaluated using Langmuir and Freundlich isotherm models. The surface morphology of groundnut shell revealed porous pores indicatives of available sites for sorption of metal ion on the surface of the groundnut shell. The adsorption kinetics of the metals ions followed pseudo-first-order with average rate constants of 5.63 × 10-2. Langmuir adsorption isotherm fitted the isotherm study with R 2 >0.9 while the maximum adsorption capacities of 23.46 mg g-1. Negative values of ΔG° obtained from thermodynamic evaluations revealed that the adsorption process is spontaneous. The values ΔH° and ΔS° obtained respectively are 29.90 and 105 J mol-1 K-1. Prediction of regression models was in good agreement with experimental result. This study showed that groundnut shell to be a good adsorbent for the removal of Zn(II) from aqueous solution.

Research paper thumbnail of Magnetic core layered double hydroxide over halloysite as a robust adsorbent for the treatment of dye-contaminated wastewater: a clean approach for industrial applications

DESALINATION AND WATER TREATMENT, 2019

Research paper thumbnail of Impregnation of zinc oxide modified clay over alginate beads: a novel material for the effective removal of congo red from wastewater

RSC Advances, 2017

Alginate hydrogel beads were impregnated with zinc oxide (ZnO) modified sepiolite clay and applie... more Alginate hydrogel beads were impregnated with zinc oxide (ZnO) modified sepiolite clay and applied for the removal of congo red (CR) dye from its aqueous solution in batch and packed column systems.

Research paper thumbnail of Hydrothermally grown ZnO nanoparticles for effective photocatalytic activity

Applied Surface Science, 2017

Research paper thumbnail of Current progress on bio-based polymers and their future trends

Progress in Biomaterials, 2013

Research paper thumbnail of Studies on L-valinium Picrate Single Crystal: A Promising NLO Crystal

Journal of Minerals and Materials Characterization and Engineering, 2009

Research paper thumbnail of Structural and Optical Characterization Studies on 2, 4- dinitrophenylhydrazine Single Crystal

Journal of Minerals and Materials Characterization and Engineering, 2010

Research paper thumbnail of Low power optical limiting studies on nanocrystalline benzimidazole thin films prepared by modified liquid phase growth technique

Bulletin of Materials Science, 2015

Research paper thumbnail of Role of SDS surfactant concentrations on the structural, morphological, dielectric and magnetic properties of CoFe2O4 nanoparticles

RSC Advances, 2015

Schematic illustration of the synthesis of sodium dodecyl sulfate (SDS) added to cobalt ferrite (... more Schematic illustration of the synthesis of sodium dodecyl sulfate (SDS) added to cobalt ferrite (CoFe2O4) magnetic nanoparticles at various concentrations (0.04 and 0.08 M) and their morphological and magnetic characterizations.

Research paper thumbnail of 4-Fluoro-N-(4-hy-droxy-benzyl-idene)aniline

Acta crystallographica. Section E, Structure reports online, 2014

In the title compound, C13H10FNO, the benzene ring planes are inclined at an angle of 50.52 (8)°.... more In the title compound, C13H10FNO, the benzene ring planes are inclined at an angle of 50.52 (8)°. A characteristic of aromatic Schiff bases with N-aryl substituents is that the terminal phenyl rings are twisted relative to the plane of the HC=N link between them. In this case, the HC=N unit makes dihedral angles of 10.6 (2) and 40.5 (2)° with the hy-droxy-benzene and fluro-benzene rings, respectively. In the crystal, O-H⋯N and C-H⋯F hydrogen bonds lead to the formation of chains along the c- and b-axis directions, respectively. C-H⋯π contacts link mol-ecules along a and these contacts combine to generate a three-dimensional network with mol-ecules stacked along the b-axis direction.

Research paper thumbnail of Up-Cycling of PET (Polyethylene Terephthalate) to the Biodegradable Plastic PHA (Polyhydroxyalkanoate)

Environmental Science & Technology, 2008

Research paper thumbnail of The anti-cancer activity of a cationic anti-microbial peptide derived from monomers of polyhydroxyalkanoate

Biomaterials, 2013

The biodegradable polymer medium chain length polyhydroxyalkanoate (mclPHA), produced by Pseudomo... more The biodegradable polymer medium chain length polyhydroxyalkanoate (mclPHA), produced by Pseudomonas putida CA-3, was depolymerised and the predominant monomer (R)-3-hydroxydecanoic acid (R10) purified. R10 was conjugated to a D-peptide DP18 and its derivatives. All peptides conjugated with R10 exhibited greater anti-cancer activity compared to the unconjugated peptides. Unconjugated and conjugated peptides were cytocidal for cancer cells. Conjugation of R10 to peptides was essential for enhanced anti-proliferation activity, as unconjugated mixes did not result in enhancement of anti-cancer activity. The conjugation of R10 resulted in more rapid uptake of peptides into HeLa and MiaPaCa cells compared to unconjugated peptide. Both unconjugated and R10 conjugated peptides localized to the mitochondria of HeLa and MiaPaCa cells and induced apoptosis. Peptide conjugated with a terminally hydroxylated decanoic acid (u-hydroxydecanoic acid) exhibited 3.3 and 6.3 fold higher IC 50 values compared to R10 conjugated peptide indicating a role for the position of the hydroxyl moiety in enhancement of anti-cancer activity. Conjugation of decanoic acid (C10) to peptides resulted in similar or higher IC 50 values compared to R10 conjugates but C10 conjugates did not exhibit any cancer selectivity. Combination studies showed that R10DP18L exhibited synergy with cisplatin, gemcitabine, and taxotere with IC 50 values in the nanomolar range.

Research paper thumbnail of Identification and characterization of an acyl-CoA dehydrogenase from Pseudomonas putida KT2440 that shows preference towards medium to long chain length fatty acids

Microbiology, 2014

Diverse and elaborate pathways for nutrient utilization, as well as mechanisms to combat unfavour... more Diverse and elaborate pathways for nutrient utilization, as well as mechanisms to combat unfavourable nutrient conditions makePseudomonas putidaKT2440 a versatile micro-organism able to occupy a range of ecological niches. The fatty acid degradation pathway ofP. putidais complex and correlated with biopolymer medium chain length polyhydroxyalkanoate (mcl-PHA) biosynthesis. Little is known about the second step of fatty acid degradation (β-oxidation) in this strain.In silicoanalysis of its genome sequence revealed 21 putative acyl-CoA dehydrogenases (ACADs), four of which were functionally characterized through mutagenesis studies. Four mutants with insertionally inactivated ACADs (PP_1893, PP_2039, PP_2048 and PP_2437) grew and accumulated mcl-PHA on a range of fatty acids as the sole source of carbon and energy. Their ability to grow and accumulate biopolymer was differentially negatively affected on various fatty acids, in comparison to the wild-type strain. Inactive PP_2437 exhib...

Research paper thumbnail of Biowaste-Derived Hydroxyapatite for Effective Removal of Reactive Yellow 4 Dye: Equilibrium, Kinetic, and Thermodynamic Studies

ACS Omega, 2018

This study examines the application of poultry eggshell (PES) as a source of calcium for the synt... more This study examines the application of poultry eggshell (PES) as a source of calcium for the synthesis of hydroxyapatite (HA) via annealation. The synthesized powder (poultry eggshell hydroxyapatite (PESHA)) was characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR), scanning electron microscopy (SEM), EDAX, and transmission electron microscopy (TEM) analytical techniques. This powder was used for adsorptive removal of the Reactive Yellow 4 (RY4) dye in a batch process. Results from morphological analysis by SEM and TEM revealed that the microstructure of the apatite is made up of needle−rod-like particles with the length of 15−60 nm, breadth of 4−6 nm, and crystallite size of 86.32 nm. EDAX revealed that HA has Ca/P ratio of 1.63, indicating a nonstoichiometric apatite, whereas XRD analysis presented it as a pure monophasic hydroxyapatite powder. Fourier Transform Infrared (FTIR) spectroscopy indicated that the adsorption is due to the electrostatic interaction between the functional groups of the dye and those on the apatite surface. The maximum adsorption capacity (Q max) of 127.9 mg g −1 was obtained for the adsorption process, whereas the pseudo-first-order model with R 2 > 0.99 best described the adsorption mechanism. Furthermore, the thermodynamic studies revealed that the adsorption process was exothermic and spontaneous in nature with ΔH and ΔS values of 120.79 kJ mol −1 and 0.395 kJ mol −1 K −1 , respectively. Thus, hydroxyapatite fabricated from the poultry waste of eggshell can be effectively utilized as an excellent nontoxic and cheap adsorbent for the removal of RY4 dye from aqueous medium.

Research paper thumbnail of Morphometric Study of Maxillary Sinuses in Normal Subjects by Using Computed Tomographic Images

International Journal of Anatomy and Research

Research paper thumbnail of Computed tomographic study of sphenoid sinus and its septations

Indian Journal of Clinical Anatomy and Physiology

Introduction: Knowledge of sphenoid sinus anatomy and its variations is of prime importance in tr... more Introduction: Knowledge of sphenoid sinus anatomy and its variations is of prime importance in transsphenoidal endoscopic skull base surgery. Aim: The aim of the present study was to measure the bilateral sphenoidal sinus parameters [depth, width, and height] and determine the number and pattern of attachments of intra-sphenoid sinus septations in 52 subjects by computed tomography. Materials and Methods: Cranial computed tomographic images of 52 normal subjects were included in our study. Four cases in whom the septations were absent were excluded from the measurement of dimensions of the sinus. The depth, width, and height in 48 sphenoidal sinuses were measured electronically. The coronal and axial sections were taken and subsequently examined. Results: The mean depth, width, and height of sphenoid sinus in males on right side are 2.2458cm, 1.555cm, 1.9044 cm and on left side are 2.3877cm, 1.6519cm, 1.8613cm and in females on right side are 2.0475cm, 1.6258cm,2.05cm and on left side are 2.066cm, 1.2891cm and 1.7941 cm respectively. We noted single septum in 75%cases, double septa in 11.53%case, multiple septa in 5.76% cases and absence of septa in 7.69% cases.

Research paper thumbnail of Organ Segmentation of Fetal MR Images Using Active Contours and Morphology

ABSTRACT BACKGROUND Previous work performed on fetal MRI use apriori information that is typicall... more ABSTRACT BACKGROUND Previous work performed on fetal MRI use apriori information that is typically dependent on contrast [1]. An algorithm, which is not restricted by such dependence would enable seamless application of segmentation approaches for different MR contrast types. EVALUATION A database containing 6 MRI volumes of fetuses was used for this study. All images were acquired with the single shot Fast Spin Echo sequence on a 1.5T GE MR scanner. Acquisition parameters were: TR/TE=1750/91.616 ms, flip angle = 90, slice thickness/gap = 4/5 mm. Region of interest (ROI)was selected for the input image and segmentation was performed using active contour method. The number of iterations and smoothing parameter for the active contour were optimized for our algorithm based on 1 volume.Post-processing was performed using morphological operations of opening and closing. Manual and semi-automatic segmentation of the brain and the lungs were performed on the 6 datasets and were compared.The mean and standard deviation for the brain are calculated for each slice from 6 different datasets. On the other hand, lungs can be segmented out clearly only in case of sagittal view with respect to fetus. Lungs were clearly visible in 2 datasets out of 6. Three different slices were selected from each of these datasets, which had sagittal view for quantification. DISCUSSION The implemented algorithm resulted in segmentation of the brain(2630±364.08) and lung(558.36±231) that is similar to area of segmentation as obtained manually (2819±274.71), (513.15±243.59) respectively for both cases.The output of our algorithm can also be seen in the figure attached 1(d). The figure also contains the results of segmentation for a representative data set showing the fetus (a), segmented brain (b) and segmented lungs (c). CONCLUSION We have proposed asupervised method for the contrast independent segmentation of fetal brain and lungs. The proposed method does not depend on prior information such as eye-localization, which is highly contrast dependent. The results of comparison of the manual and semi-automated segmentation show the utility of the approach. Current and future work involves automation of ROI, 3D reconstruction and volumetric analysis.

Research paper thumbnail of Region of Interest Compressed Sensing MRI

Journal of the Indian Institute of Science, Oct 1, 2014

Compressed Sensing (CS) based Magnetic Resonance Imaging (MRI) reconstruction relies on data spar... more Compressed Sensing (CS) based Magnetic Resonance Imaging (MRI) reconstruction relies on data sparsity. Region of Interest Compressed Sensing (ROICS) is based on the hypothesis that superior CS performance can be obtained by limiting the sparsity objective and data consistency in CS to a Region of Interest (ROI). This relaxation is justified in most applications where the anatomy of interest such as the heart, has surrounding structures, typically not used for further analyses. ROICS has been proposed as an extension of CS that is ROI weighted CS. Current work demonstrates the implementation of ROICS for the first time on MR cardiac and brain data. Reconstructed images and performance evaluation metrics show that ROICS technique performs better than conventional CS technique. CS and Parallel Imaging (PI) are widely used to reduce MRI scan time and their combination yields better performance than used individually. The proposed method also implements the combination of ROICS and SENSitivity Encoding (SENSE), which applies weighted CS to a particular ROI, and the resulting output is then reconstructed using SENSE for arbitrary k-space. Proposed ROICS-PI performs better as compared to PI and CS + PI.

Research paper thumbnail of Total synthesis of chamigrene and laurencenone C via Ireland ester Claisen rearrangement and an intramolecular type II carbonyl ene reaction sequence

Tetrahedron, 2008

A combination of Ireland ester Claisen rearrangement and intramolecular type II carbonyl ene reac... more A combination of Ireland ester Claisen rearrangement and intramolecular type II carbonyl ene reactions were exploited for the total synthesis of chamigrenes containing a quaternary carbon atom next to the spirocentre in spiro[5.5]undecane.

Research paper thumbnail of Effect of pH on the morphology, mechanical and optical properties of L-arginine monohydrobromide monohydrate (LAHBr) single crystals

Bulletin of Materials Science, Sep 1, 2015

Research paper thumbnail of Agro waste material as ecofriendly adsorbent for the removal of Zn(II): isotherm, kinetic, thermodynamic and optimization studies

DESALINATION AND WATER TREATMENT, 2019

Contamination of environment by heavy metals posed significant threat to human, animals and plant... more Contamination of environment by heavy metals posed significant threat to human, animals and plants health due their accumulation in the living tissues and their non-degradability. Excess of zinc in living system is detrimental to health adverse effects therefore; this work investigates the feasibility of removal of Zn 2+ from aqueous solution using agricultural biowaste adsorbent prepared from groundnut shell. Effects of some important parameters such as pH, initial metal concentrations, temperature and adsorbent dosage on adsorption process were investigated. These factors were optimized by Box-Behnken experimental design using Design Expert 6.0. The prepared biosorbent was characterized using Scanning electron microscopy (SEM), Fourier Transform Infrared (FT-IR) and X-ray dispersion (XRD). Data from kinetic study was analyzed with pseudo-first-order and pseudo-second-order kinetic models while equilibrium data were evaluated using Langmuir and Freundlich isotherm models. The surface morphology of groundnut shell revealed porous pores indicatives of available sites for sorption of metal ion on the surface of the groundnut shell. The adsorption kinetics of the metals ions followed pseudo-first-order with average rate constants of 5.63 × 10-2. Langmuir adsorption isotherm fitted the isotherm study with R 2 >0.9 while the maximum adsorption capacities of 23.46 mg g-1. Negative values of ΔG° obtained from thermodynamic evaluations revealed that the adsorption process is spontaneous. The values ΔH° and ΔS° obtained respectively are 29.90 and 105 J mol-1 K-1. Prediction of regression models was in good agreement with experimental result. This study showed that groundnut shell to be a good adsorbent for the removal of Zn(II) from aqueous solution.

Research paper thumbnail of Magnetic core layered double hydroxide over halloysite as a robust adsorbent for the treatment of dye-contaminated wastewater: a clean approach for industrial applications

DESALINATION AND WATER TREATMENT, 2019

Research paper thumbnail of Impregnation of zinc oxide modified clay over alginate beads: a novel material for the effective removal of congo red from wastewater

RSC Advances, 2017

Alginate hydrogel beads were impregnated with zinc oxide (ZnO) modified sepiolite clay and applie... more Alginate hydrogel beads were impregnated with zinc oxide (ZnO) modified sepiolite clay and applied for the removal of congo red (CR) dye from its aqueous solution in batch and packed column systems.

Research paper thumbnail of Hydrothermally grown ZnO nanoparticles for effective photocatalytic activity

Applied Surface Science, 2017

Research paper thumbnail of Current progress on bio-based polymers and their future trends

Progress in Biomaterials, 2013

Research paper thumbnail of Studies on L-valinium Picrate Single Crystal: A Promising NLO Crystal

Journal of Minerals and Materials Characterization and Engineering, 2009

Research paper thumbnail of Structural and Optical Characterization Studies on 2, 4- dinitrophenylhydrazine Single Crystal

Journal of Minerals and Materials Characterization and Engineering, 2010

Research paper thumbnail of Low power optical limiting studies on nanocrystalline benzimidazole thin films prepared by modified liquid phase growth technique

Bulletin of Materials Science, 2015

Research paper thumbnail of Role of SDS surfactant concentrations on the structural, morphological, dielectric and magnetic properties of CoFe2O4 nanoparticles

RSC Advances, 2015

Schematic illustration of the synthesis of sodium dodecyl sulfate (SDS) added to cobalt ferrite (... more Schematic illustration of the synthesis of sodium dodecyl sulfate (SDS) added to cobalt ferrite (CoFe2O4) magnetic nanoparticles at various concentrations (0.04 and 0.08 M) and their morphological and magnetic characterizations.

Research paper thumbnail of 4-Fluoro-N-(4-hy-droxy-benzyl-idene)aniline

Acta crystallographica. Section E, Structure reports online, 2014

In the title compound, C13H10FNO, the benzene ring planes are inclined at an angle of 50.52 (8)°.... more In the title compound, C13H10FNO, the benzene ring planes are inclined at an angle of 50.52 (8)°. A characteristic of aromatic Schiff bases with N-aryl substituents is that the terminal phenyl rings are twisted relative to the plane of the HC=N link between them. In this case, the HC=N unit makes dihedral angles of 10.6 (2) and 40.5 (2)° with the hy-droxy-benzene and fluro-benzene rings, respectively. In the crystal, O-H⋯N and C-H⋯F hydrogen bonds lead to the formation of chains along the c- and b-axis directions, respectively. C-H⋯π contacts link mol-ecules along a and these contacts combine to generate a three-dimensional network with mol-ecules stacked along the b-axis direction.

Research paper thumbnail of Up-Cycling of PET (Polyethylene Terephthalate) to the Biodegradable Plastic PHA (Polyhydroxyalkanoate)

Environmental Science & Technology, 2008

Research paper thumbnail of The anti-cancer activity of a cationic anti-microbial peptide derived from monomers of polyhydroxyalkanoate

Biomaterials, 2013

The biodegradable polymer medium chain length polyhydroxyalkanoate (mclPHA), produced by Pseudomo... more The biodegradable polymer medium chain length polyhydroxyalkanoate (mclPHA), produced by Pseudomonas putida CA-3, was depolymerised and the predominant monomer (R)-3-hydroxydecanoic acid (R10) purified. R10 was conjugated to a D-peptide DP18 and its derivatives. All peptides conjugated with R10 exhibited greater anti-cancer activity compared to the unconjugated peptides. Unconjugated and conjugated peptides were cytocidal for cancer cells. Conjugation of R10 to peptides was essential for enhanced anti-proliferation activity, as unconjugated mixes did not result in enhancement of anti-cancer activity. The conjugation of R10 resulted in more rapid uptake of peptides into HeLa and MiaPaCa cells compared to unconjugated peptide. Both unconjugated and R10 conjugated peptides localized to the mitochondria of HeLa and MiaPaCa cells and induced apoptosis. Peptide conjugated with a terminally hydroxylated decanoic acid (u-hydroxydecanoic acid) exhibited 3.3 and 6.3 fold higher IC 50 values compared to R10 conjugated peptide indicating a role for the position of the hydroxyl moiety in enhancement of anti-cancer activity. Conjugation of decanoic acid (C10) to peptides resulted in similar or higher IC 50 values compared to R10 conjugates but C10 conjugates did not exhibit any cancer selectivity. Combination studies showed that R10DP18L exhibited synergy with cisplatin, gemcitabine, and taxotere with IC 50 values in the nanomolar range.

Research paper thumbnail of Identification and characterization of an acyl-CoA dehydrogenase from Pseudomonas putida KT2440 that shows preference towards medium to long chain length fatty acids

Microbiology, 2014

Diverse and elaborate pathways for nutrient utilization, as well as mechanisms to combat unfavour... more Diverse and elaborate pathways for nutrient utilization, as well as mechanisms to combat unfavourable nutrient conditions makePseudomonas putidaKT2440 a versatile micro-organism able to occupy a range of ecological niches. The fatty acid degradation pathway ofP. putidais complex and correlated with biopolymer medium chain length polyhydroxyalkanoate (mcl-PHA) biosynthesis. Little is known about the second step of fatty acid degradation (β-oxidation) in this strain.In silicoanalysis of its genome sequence revealed 21 putative acyl-CoA dehydrogenases (ACADs), four of which were functionally characterized through mutagenesis studies. Four mutants with insertionally inactivated ACADs (PP_1893, PP_2039, PP_2048 and PP_2437) grew and accumulated mcl-PHA on a range of fatty acids as the sole source of carbon and energy. Their ability to grow and accumulate biopolymer was differentially negatively affected on various fatty acids, in comparison to the wild-type strain. Inactive PP_2437 exhib...

Research paper thumbnail of Biowaste-Derived Hydroxyapatite for Effective Removal of Reactive Yellow 4 Dye: Equilibrium, Kinetic, and Thermodynamic Studies

ACS Omega, 2018

This study examines the application of poultry eggshell (PES) as a source of calcium for the synt... more This study examines the application of poultry eggshell (PES) as a source of calcium for the synthesis of hydroxyapatite (HA) via annealation. The synthesized powder (poultry eggshell hydroxyapatite (PESHA)) was characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR), scanning electron microscopy (SEM), EDAX, and transmission electron microscopy (TEM) analytical techniques. This powder was used for adsorptive removal of the Reactive Yellow 4 (RY4) dye in a batch process. Results from morphological analysis by SEM and TEM revealed that the microstructure of the apatite is made up of needle−rod-like particles with the length of 15−60 nm, breadth of 4−6 nm, and crystallite size of 86.32 nm. EDAX revealed that HA has Ca/P ratio of 1.63, indicating a nonstoichiometric apatite, whereas XRD analysis presented it as a pure monophasic hydroxyapatite powder. Fourier Transform Infrared (FTIR) spectroscopy indicated that the adsorption is due to the electrostatic interaction between the functional groups of the dye and those on the apatite surface. The maximum adsorption capacity (Q max) of 127.9 mg g −1 was obtained for the adsorption process, whereas the pseudo-first-order model with R 2 > 0.99 best described the adsorption mechanism. Furthermore, the thermodynamic studies revealed that the adsorption process was exothermic and spontaneous in nature with ΔH and ΔS values of 120.79 kJ mol −1 and 0.395 kJ mol −1 K −1 , respectively. Thus, hydroxyapatite fabricated from the poultry waste of eggshell can be effectively utilized as an excellent nontoxic and cheap adsorbent for the removal of RY4 dye from aqueous medium.

Research paper thumbnail of Morphometric Study of Maxillary Sinuses in Normal Subjects by Using Computed Tomographic Images

International Journal of Anatomy and Research

Research paper thumbnail of Computed tomographic study of sphenoid sinus and its septations

Indian Journal of Clinical Anatomy and Physiology

Introduction: Knowledge of sphenoid sinus anatomy and its variations is of prime importance in tr... more Introduction: Knowledge of sphenoid sinus anatomy and its variations is of prime importance in transsphenoidal endoscopic skull base surgery. Aim: The aim of the present study was to measure the bilateral sphenoidal sinus parameters [depth, width, and height] and determine the number and pattern of attachments of intra-sphenoid sinus septations in 52 subjects by computed tomography. Materials and Methods: Cranial computed tomographic images of 52 normal subjects were included in our study. Four cases in whom the septations were absent were excluded from the measurement of dimensions of the sinus. The depth, width, and height in 48 sphenoidal sinuses were measured electronically. The coronal and axial sections were taken and subsequently examined. Results: The mean depth, width, and height of sphenoid sinus in males on right side are 2.2458cm, 1.555cm, 1.9044 cm and on left side are 2.3877cm, 1.6519cm, 1.8613cm and in females on right side are 2.0475cm, 1.6258cm,2.05cm and on left side are 2.066cm, 1.2891cm and 1.7941 cm respectively. We noted single septum in 75%cases, double septa in 11.53%case, multiple septa in 5.76% cases and absence of septa in 7.69% cases.

Research paper thumbnail of Organ Segmentation of Fetal MR Images Using Active Contours and Morphology

ABSTRACT BACKGROUND Previous work performed on fetal MRI use apriori information that is typicall... more ABSTRACT BACKGROUND Previous work performed on fetal MRI use apriori information that is typically dependent on contrast [1]. An algorithm, which is not restricted by such dependence would enable seamless application of segmentation approaches for different MR contrast types. EVALUATION A database containing 6 MRI volumes of fetuses was used for this study. All images were acquired with the single shot Fast Spin Echo sequence on a 1.5T GE MR scanner. Acquisition parameters were: TR/TE=1750/91.616 ms, flip angle = 90, slice thickness/gap = 4/5 mm. Region of interest (ROI)was selected for the input image and segmentation was performed using active contour method. The number of iterations and smoothing parameter for the active contour were optimized for our algorithm based on 1 volume.Post-processing was performed using morphological operations of opening and closing. Manual and semi-automatic segmentation of the brain and the lungs were performed on the 6 datasets and were compared.The mean and standard deviation for the brain are calculated for each slice from 6 different datasets. On the other hand, lungs can be segmented out clearly only in case of sagittal view with respect to fetus. Lungs were clearly visible in 2 datasets out of 6. Three different slices were selected from each of these datasets, which had sagittal view for quantification. DISCUSSION The implemented algorithm resulted in segmentation of the brain(2630±364.08) and lung(558.36±231) that is similar to area of segmentation as obtained manually (2819±274.71), (513.15±243.59) respectively for both cases.The output of our algorithm can also be seen in the figure attached 1(d). The figure also contains the results of segmentation for a representative data set showing the fetus (a), segmented brain (b) and segmented lungs (c). CONCLUSION We have proposed asupervised method for the contrast independent segmentation of fetal brain and lungs. The proposed method does not depend on prior information such as eye-localization, which is highly contrast dependent. The results of comparison of the manual and semi-automated segmentation show the utility of the approach. Current and future work involves automation of ROI, 3D reconstruction and volumetric analysis.

Research paper thumbnail of Region of Interest Compressed Sensing MRI

Journal of the Indian Institute of Science, Oct 1, 2014

Compressed Sensing (CS) based Magnetic Resonance Imaging (MRI) reconstruction relies on data spar... more Compressed Sensing (CS) based Magnetic Resonance Imaging (MRI) reconstruction relies on data sparsity. Region of Interest Compressed Sensing (ROICS) is based on the hypothesis that superior CS performance can be obtained by limiting the sparsity objective and data consistency in CS to a Region of Interest (ROI). This relaxation is justified in most applications where the anatomy of interest such as the heart, has surrounding structures, typically not used for further analyses. ROICS has been proposed as an extension of CS that is ROI weighted CS. Current work demonstrates the implementation of ROICS for the first time on MR cardiac and brain data. Reconstructed images and performance evaluation metrics show that ROICS technique performs better than conventional CS technique. CS and Parallel Imaging (PI) are widely used to reduce MRI scan time and their combination yields better performance than used individually. The proposed method also implements the combination of ROICS and SENSitivity Encoding (SENSE), which applies weighted CS to a particular ROI, and the resulting output is then reconstructed using SENSE for arbitrary k-space. Proposed ROICS-PI performs better as compared to PI and CS + PI.