Shubham Srivastava - Academia.edu (original) (raw)
Papers by Shubham Srivastava
Cureus, 2021
Background and objective Osteoarthritis (OA) is a polyarticular disease that most commonly afflic... more Background and objective Osteoarthritis (OA) is a polyarticular disease that most commonly afflicts the knee joint. Established operative treatment options for medial joint OA of the knee include high tibial osteotomy, unicompartmental knee arthroplasty, and total knee arthroplasty. Proximal fibular osteotomy (PFO) is a relatively new procedure for treating medial joint OA of the knee. The objective of this study was to describe the functional and radiological outcomes at one year in patients undergoing PFO for medial joint OA of the knee. Materials and methods The study included 21 patients with medial joint OA of the knee who underwent PFO. Visual analog scale (VAS) score, medial to lateral knee joint space ratio (ML ratio), Kellgren-Lawrence (KL) grade, and the American Knee Society Score (AKSS) (clinical and functional) were recorded preoperatively. VAS score, ML ratio, and AKSS (clinical and functional) were documented again at the three-month and one-year followups. Results The mean age of the patients was 58.85 ±6.94 years; 12 (57.1%) were female and nine (42.9%) were males. The mean VAS score for pain decreased from 7.86 ±0.66 at baseline to 5.14 ±1.15 at three months (p<0.001) and 3.78 ±1.26 at one year (p<0.001). The mean clinical AKSS was 56.49 ±6.95 at baseline, which increased to 63.41 ±6.20 at three months (p<0.001) and 72.71 ±9.87 at one year (p<0.001). The mean functional AKSS at baseline was 48.24 ±14.31, which increased to 60.10 ±14.81 at three months (p<0.001) and 71.46 ±15.18 at one year (p<0.001). The mean ML ratio at baseline was 0.33 ±0.19, which increased to 0.41 ±0.20 at three months (p<0.01) and 0.51 ±0.22 at one year (p<0.001). Conclusion In patients who undergo PFO for OA of the knee, improvements in VAS score for pain, AKSS (functional and clinical), and ML ratio were observed to be maintained for a period of one year postoperatively.
International Conference on Intelligent Data Communication Technologies and Internet of Things (ICICI) 2018, 2018
As per Government of the India ministry of road transport & highways transport research wing-2016... more As per Government of the India ministry of road transport & highways transport research wing-2016 Report shows that 403598 accidents happen because of only Driver faults. Out of that 121126 peoples are killed. This paper describes an algorithm as well as implemented system for accurate and fast Driver-assistance system (DAS) that detects obstacles and applies the automatic break as well as gives SMS alert to family and service center also vehicle tracking status with system parameters. A prototype of the system is going on in the laboratory with some real time Prospective. Ultrasonic sensors are used to detect obstacles. This system having several advantages over other types of sensors in short-range object detection. As per the Ultrasonic system will be applied break automatically. Vibration sensor used to active GSM Module for alertness. Multiple sensors are needed to get 360 rotation safety of the vehicle. Furthermore, the driver of the vehicle is cannot see the system parameter....
Journal of Pharmacognosy and Phytochemistry, 2018
This experiment was carried out to determine the effects of PSB and rhizobium inoculation for a C... more This experiment was carried out to determine the effects of PSB and rhizobium inoculation for a Chickpea (Cicer arietinum L.) variety, Awarodhi, under Central Uttar Pradesh conditions in 2015 and 2016. The trial was laid out in factorial randomized block design with three replications. The experiment on the chickpea (Cicer arietinum L.) crop was conducted at Nawabganj Research Farm of Chandra Shekhar Azad University of Agriculture and Technology, Kanpur (U.P.) during Rabi season for year 2015-16, to assess the response of Rhizobium and PSB as affected by their application. The result shows that some plant attributes of the crop like the number of nodules varied from 8 to 25 at 30 days and 12 to 43 at 60 days. The yield of the crop was also varied from 12 to 26 qtl. ha of seeds of chickpea (Cicer arietinum L.) and 13.7 to 35.0 qtl. ha Stover of the crop. Maximum N and P uptake in grain and straw as well as protein content in grain were noted maximum with dual inoculation of (Rhizobiu...
Journal of Plant Nutrition, 2021
Abstract Deficiency and toxicity of micronutrient boron (B) play a critical role in plant product... more Abstract Deficiency and toxicity of micronutrient boron (B) play a critical role in plant productivity. In this study, the evaluation of B supplementation on biomass and essential oil (EO) yield of rose-scented geranium (Pelargonium graveolens L.) and its distribution at different application rates (2.5, 5.0, and 7.5 kg ha−1) was performed in a field trial during the growing season of two consecutive years 2017–18 and 2018–19. Boron uptake, plant biomass, and EO yield along with EO constituent in leaves were determined at different time scales. Application of B significantly improved the biomass yield of P. graveolens and at B-II treatment (5.0 kg ha−1 dose) highest biomass and EO yield was recorded, however, B-III treatment (7.5 kg ha−1) demonstrated toxicity symptoms like the decline in protein and chlorophyll content and an increase in proline and stress enzymes (SOD, CAT) in plant leaves. The effects of B on EO constituents varied with the different developmental stages of P. graveolens. Furthermore, the application of B at 5.0 kg ha−1 acts as a stimulant in upgrading the quality and quantity of EO with improved main aroma constituent’s P. graveolens than the control without modulating odor quality i.e., citronellol:geraniol (C:G) ratio. Hence, the study revealed a balanced level of B as a crucial parameter for the enhanced productivity with the improved economic return of P. graveolens.
Physical Review D, 2020
X-ray reflection spectroscopy is a promising technique for testing general relativity in the stro... more X-ray reflection spectroscopy is a promising technique for testing general relativity in the strong field regime, as it can be used to test the Kerr black hole hypothesis. In this context, the parametrically deformed black hole metrics proposed by Konoplya, Rezzolla & Zhidenko (Phys. Rev. D93, 064015, 2016) form an important class of non-Kerr black holes. We implement this class of black hole metrics in relxill nk, which is a framework we have developed for testing for non-Kerr black holes using X-ray reflection spectroscopy. We perform a qualitative analysis of the effect of the leading order strong-field deformation parameters on typical observables like the innermost stable circular orbits and the reflection spectra. We also present the first X-ray constraints on some of the deformation parameters of this metric, using Suzaku data from the supermassive black hole in Ark 564, and compare them with those obtained (or expected) from other observational techniques like gravitational waves and black hole imaging.
Optik, 2021
Abstract The prime theme of this work is to explore the excitation wavelength dependent photolumi... more Abstract The prime theme of this work is to explore the excitation wavelength dependent photoluminescence characteristics and white light generation in activators [europium (Eu) and terbium (Tb)] doped yttrium borate (YBO3) phosphors. In order to study the influence of excitation wavelength on photoluminescence emission intensity, a fixed amount (5 mol%) of Tb and different concentration of Eu (1, 2, 3, 5 and 7 mol%) were co-doped into yttrium borate (YBO3) host matrix via a solution precursor route using sodium borohydride as a precipitating agent. The ratio of Tb and Eu emission peaks suggests that it is possible to produce multi-color emissions including white light. The excitation dependence of emission comes from the combined contribution of host, activator and energy transfer between host to activator as well as among individual activators, which gives rise to change in output emission color. Moreover, the optimum composition i.e. 3 mol% Eu, 5 mol% Tb co-doped YBO3 was found to be appropriate for white light emitting phosphor.
Materials Chemistry and Physics, 2020
This work explores the effect of milling on morphology and PL of Eu-doped YBO 3. � Crystallite an... more This work explores the effect of milling on morphology and PL of Eu-doped YBO 3. � Crystallite and particle size of Eu-doped YBO 3 decreases with milling time. � Particles get ruptured and shattered to nanoscale range during milling. � Smaller particles with surface disorder due to milling causes an increase of R/ O. � Excitation wavelength of 254 nm suggests better CIE and samples are red in color.
Biofilms have significant role in microbial persistence, antibiotic resistance and chronic infect... more Biofilms have significant role in microbial persistence, antibiotic resistance and chronic infections; consequently, there is a pressing need for development of novel “anti-biofilm strategies”. One of the fundamental mechanisms involved in biofilm formation is protein-protein interactions of ‘amyloid like proteins’ (ALPs) in extracellular matrix. Such interactions could be potential targets for development of novel anti-biofilm strategies; therefore, assessing the structural features of these interactions could be of great scientific value. Characterization of biomolecular interaction with conventional structure biology tools including X-Ray diffraction and Nuclear Magnetic Resonance is technically challenging, expensive and time-consuming. In contrast, modelling such interactions is time-efficient, economical and might provide deeper understanding of structural basis of interactions. Therefore, during the present study, protein-protein interaction of TasA(28-261)–TapA(33-253) (whic...
Materials Today: Proceedings, 2018
In this paper, the effect of heat treatment and warmuni-axially compression of AA 2014 alloy were... more In this paper, the effect of heat treatment and warmuni-axially compression of AA 2014 alloy were studied at different amount of deformations. Microstructural characterization and mechanical properties were studied for deformed and precipitation hardened specimens. Differential scanning calorimetry test was performed to check thermal stability of specimen, and observed that thermal stability of precipitation hardened specimen is highest. Wear test was conducted with the help of pin on disc wear testing machine, and observed that wear rate was increased with increasing load, and also precipitation hardened and deformed specimens were more wear resistant as compared to as-received material.
Journal of Biomolecular Structure and Dynamics, 2019
Abstract Prolyl oligopeptidase (POP) enzyme has been studied for various disorders, viz. Schizoph... more Abstract Prolyl oligopeptidase (POP) enzyme has been studied for various disorders, viz. Schizophrenia, Alzheimer’s, Parkinson’s, Depression, Inflammation, etc., for three decades, but no drug has passed through the clinical trials, possibly because of indigent pharmacokinetics. This might have been a result of similar structures of drug candidates. This study aimed at identifying novel small non-peptidomimetic inhibitors for POP enzyme that could serve as a lead for developing newer drugs. Structure-based virtual screening of molecules of MolMall database was conducted on the POP enzyme (PDB ID 3DDU) to identify potential hits. The hits identified were subjected to computational pharmacokinetic screening followed by molecular mechanics/generalized Born and surface area studies to estimate the binding free energy of the docked complexes. After that, nine hits were selected and tested for POP inhibitory activity, among which one compound MM 4 was found to be most potent with EC50 of 100 µM. Compound MM 4 was further subjected to molecular dynamics simulations to study the overall stability of the ligand–protein complex. The compound interacted strongly with catalytic amino acid Arg643 by forming salt and water bridges; it also interacted well with amino acids Phe173, Arg252 and Met235. This study provides a lead molecule for further development of POP inhibitors. Communicated by Ramaswamy H. Sarma
International journal of biological macromolecules, Jan 9, 2018
Development of resistance against existing anti-epileptic drugs has alarmed the scientific innova... more Development of resistance against existing anti-epileptic drugs has alarmed the scientific innovators to find novel potential chemical starting points for the treatment of epilepsy and GABA inhibition is a promising drug target strategy against epilepsy. The crystal structure of a subtype-selective β3-homopentameric ligand-gated ion channel of GABA receptor has been used for the first time for screening the Asinex library for discovery of GABA agonists as potential anti-epileptic agents. Co-crystallized ligand established the involvement of part of the β7-β8 loop (Glu155 and Tyr157) and β9-β10 loop (Phe200 and Tyr205) residues as the crucial amino acids in effective binding, an essential feature, being hydrogen bond or ionic interaction with Glu155 residue. Top ranked hits were further subjected to binding energy estimation, ADMET analysis and ligand efficiency matric calculations as consecutive filters. About 19 compounds qualifying all parameters possessed interaction of one posit...
Journal of receptor and signal transduction research, Jan 31, 2017
Multidrug resistance along with side-effects of available anti-epileptic drugs and unavailability... more Multidrug resistance along with side-effects of available anti-epileptic drugs and unavailability of potent and effective agents in submicromolar quantities presents the biggest therapeutic challenges in anti-epileptic drug discovery. The molecular modeling techniques allow us to identify agents with novel structures to match the continuous urge for its discovery. KCNQ2 channel represents one of the validated targets for its therapy. The present study involves identification of newer anti-epileptic agents by means of a computer-aided drug design adaptive protocol involving both structure-based virtual screening of Asinex library using homology model of KCNQ2 and 3D-QSAR based virtual screening with docking analysis, followed by dG bind and ligand efficiency calculations with ADMET studies, of which 20 hits qualified all the criterions. The best ligands of both screenings with least potential for toxicity predicted computationally were then taken for molecular dynamic simulations. Al...
Materials science & engineering. C, Materials for biological applications, 2017
Bortezomib (BTZ) is the first proteasome inhibitor approved by the US-FDA is majorly used for the... more Bortezomib (BTZ) is the first proteasome inhibitor approved by the US-FDA is majorly used for the treatment of newly diagnosed and relapsed multiple myeloma including mantle cell lymphoma. BTZ is hydrophobic in nature and is a major cause for its minimal presence as marketed formulations. The present study reports the design, development and characterization of dendrimer based formulation for the improved solubility and effectivity of bortezomib. The study also equally focuses on the mechanistic elucidation of solubilization by two types of dendrimers i.e. fourth generation of poly (amidoamine) dendrimers (G4-PAMAM-NH2) and fifth generation of poly (propylene) imine dendrimers (G5-PPI-NH2). It was observed that aqueous solubility of BTZ was concentration and pH dependent. At 2mM G5-PPI-NH2 concentration, the fold increase in bortezomib solubility was 1152.63 times in water, while approximately 3426.69 folds increase in solubility was observed at pH10.0, respectively (p<0.05). The...
Journal of Biomolecular Structure and Dynamics, 2016
Structure-based screening approach targeting mGlu2 receptor was carried out to identify good chem... more Structure-based screening approach targeting mGlu2 receptor was carried out to identify good chemical starting points for anti-epileptic therapy. Interactive modes of final 12 compounds identified on the basis of screening of Asinex library, binding energy analysis, ADME profiling with special emphasis for CNS ranges, and toxicity analysis were studied and showed good binding modes in the mGluR2-active site. Enrichment studies for validating screening protocol were carried out which gave ROC values 0.98 (AUC = 0.96) for SP, 0.97 (AUC = 0.95) for XP with BEDROC analysis. Our results indicate that all the 12 hits showed good CNS drug-like properties, have better binding free energy and ADME profile as compared to co-crystallized ligand with the best ligand hit retaining conserved hydrogen bond interactions with Ala-166, Thr-168, Ser-145, and Arg-61 residues in bilobatevenus fly-trap domain of mGluR2 receptor. Molecular dynamics simulations proved that the two potential hits, qualifying all screening parameters, are stable in the receptor active site pocket, confirming the potential of the identified hits as a specific target for mGluR2. Because the newly discovered mGluR2 agonists are structurally different with Tc values ranging from 0.57 to 0.92, all of them can be considered for further de novo design methods.
Journal of receptor and signal transduction research, Jan 8, 2016
Biological mechanism attributing mutations in KCNQ2/Q3 results in benign familial neonatal epilep... more Biological mechanism attributing mutations in KCNQ2/Q3 results in benign familial neonatal epilepsy (BFNE), a rare form of epilepsy and thus neglected. It offers a potential target for antiepileptic drug discovery. In the present work, a pharmacophore-based 3D-QSAR model was generated for a series of N-pyridyl and pyrimidine benzamides possessing KCNQ2/Q3 opening activity. The pharmacophore model generated contains one hydrogen bond donor (D), one hydrophobic (H), and two aromatic rings (R). They are the crucial molecular write-up detailing predicted binding efficacy of high affinity and low affinity ligands for KCNQ2/Q3 opening activity. Furthermore, it has been validated by using a biological correlation between pharmacophore hypothesis-based 3D-QSAR variables and functional fingerprints of openers responsible for the receptor binding and also by docking of these benzamides into the validated homology model. Excellent statistical computational tools of QSAR model such as good corr...
Journal of Molecular Structure, 2016
High throughput virtual screening and in-silico ADMET analysis for rapid and efficient identifica... more High throughput virtual screening and in-silico ADMET analysis for rapid and efficient identification of potential PAP 248-286 aggregation inhibitors as anti-HIV agents.
Journal of Biomolecular Structure and Dynamics, 2016
Malaria is an endemic disease caused by the protozoan parasite Plasomodium falciparum. Febrifugin... more Malaria is an endemic disease caused by the protozoan parasite Plasomodium falciparum. Febrifugine analogues are natural compound obtained from the traditional Chinese herbs have shown significant antimalarial and anticancerous efficacy in experimental model. Development of resistance against the existing antimalarial drug has alarmed the scientific innovators to find a potential antimalarial molecule which can be further used by endemic countries for the elimination of this disease. In this study, structure-based virtual screening and molecular dynamics (MD) base approaches were used to generate potential antimalarial compound against plasmepsin II and prolyl-tRNA synthetase of Plasmodium. Here, we have docked series of febrifugine analogues (n = 11,395) against plasmepsin II in three different docking modes and then it was compared with previously reported target prolyl-tRNA synthetase. Extra precision docking resulted into 235 ligands having better docking score were subject for QikProp analysis. Better ligands (n = 39) obtained from QikProp analysis were subject for ADMET prediction and docking protocol validation through the estimation of receiver operator characteristics. In the later stage, 24 ligands obtained from ADMET study were subject for the estimation of binding energy through MM-GBSA and same were also docked against prolyl-tRNA synthetase to get compounds with dual inhibitor role. Finally, MD simulation and 2D fingerprint MACCS study of two best ligands have shown significant interaction with plasmepsin II and homology against known active ligand with noteworthy MACCS index, respectively. This study concludes that FA12 could be potential drug candidate to fight against Plasmodium falciparum parasites.
International Journal of Research, May 14, 2015
This paper discusses the background and application requirements that motivated the development o... more This paper discusses the background and application requirements that motivated the development of TinyOS. It enumerates the characteristics associated with any typical Networked sensor application. Technological progress in integrated, low-power, CMOS communication devices and sensors makes a rich design space of networked sensors viable.
Proceedings of the Industrial Track of the 16th International Middleware Conference, 2015
Online commerce platforms connect suppliers to customers using internet. In online travel industr... more Online commerce platforms connect suppliers to customers using internet. In online travel industry, the suppliers provide a programmatic interface for the platform to query and book travel services. Typically, multiple competitive platforms connect to the same set of suppliers and any change in inventory level leads to changes in availability and pricing. One of the key problems that online platforms deal with is to ensure the accuracy of inventory availability and pricing, while ensuring low response time to the customers. In this work, we present the design and implementation of DynaCorrect, a dynamically correcting cache for non-cooperative systems. DynaCorrect caches inventory data from remote suppliers to ensure low response time. Since the inventory price and availability may change in the background, DynaCorrect employs random sampling and a feedback loop to correct the cache. Further, in order to ensure high cache hit rate, it refreshes inventory based on popularity, spatial and temporal locality. Finally, it employs deduplication to ensure high resource efficiency for the caching system. We implemented DynaCorrect in production over a period of time and observed significant benefits to achieve the goals of high accuracy, low response time and reduced number of queries to the suppliers.
Cureus, 2021
Background and objective Osteoarthritis (OA) is a polyarticular disease that most commonly afflic... more Background and objective Osteoarthritis (OA) is a polyarticular disease that most commonly afflicts the knee joint. Established operative treatment options for medial joint OA of the knee include high tibial osteotomy, unicompartmental knee arthroplasty, and total knee arthroplasty. Proximal fibular osteotomy (PFO) is a relatively new procedure for treating medial joint OA of the knee. The objective of this study was to describe the functional and radiological outcomes at one year in patients undergoing PFO for medial joint OA of the knee. Materials and methods The study included 21 patients with medial joint OA of the knee who underwent PFO. Visual analog scale (VAS) score, medial to lateral knee joint space ratio (ML ratio), Kellgren-Lawrence (KL) grade, and the American Knee Society Score (AKSS) (clinical and functional) were recorded preoperatively. VAS score, ML ratio, and AKSS (clinical and functional) were documented again at the three-month and one-year followups. Results The mean age of the patients was 58.85 ±6.94 years; 12 (57.1%) were female and nine (42.9%) were males. The mean VAS score for pain decreased from 7.86 ±0.66 at baseline to 5.14 ±1.15 at three months (p<0.001) and 3.78 ±1.26 at one year (p<0.001). The mean clinical AKSS was 56.49 ±6.95 at baseline, which increased to 63.41 ±6.20 at three months (p<0.001) and 72.71 ±9.87 at one year (p<0.001). The mean functional AKSS at baseline was 48.24 ±14.31, which increased to 60.10 ±14.81 at three months (p<0.001) and 71.46 ±15.18 at one year (p<0.001). The mean ML ratio at baseline was 0.33 ±0.19, which increased to 0.41 ±0.20 at three months (p<0.01) and 0.51 ±0.22 at one year (p<0.001). Conclusion In patients who undergo PFO for OA of the knee, improvements in VAS score for pain, AKSS (functional and clinical), and ML ratio were observed to be maintained for a period of one year postoperatively.
International Conference on Intelligent Data Communication Technologies and Internet of Things (ICICI) 2018, 2018
As per Government of the India ministry of road transport & highways transport research wing-2016... more As per Government of the India ministry of road transport & highways transport research wing-2016 Report shows that 403598 accidents happen because of only Driver faults. Out of that 121126 peoples are killed. This paper describes an algorithm as well as implemented system for accurate and fast Driver-assistance system (DAS) that detects obstacles and applies the automatic break as well as gives SMS alert to family and service center also vehicle tracking status with system parameters. A prototype of the system is going on in the laboratory with some real time Prospective. Ultrasonic sensors are used to detect obstacles. This system having several advantages over other types of sensors in short-range object detection. As per the Ultrasonic system will be applied break automatically. Vibration sensor used to active GSM Module for alertness. Multiple sensors are needed to get 360 rotation safety of the vehicle. Furthermore, the driver of the vehicle is cannot see the system parameter....
Journal of Pharmacognosy and Phytochemistry, 2018
This experiment was carried out to determine the effects of PSB and rhizobium inoculation for a C... more This experiment was carried out to determine the effects of PSB and rhizobium inoculation for a Chickpea (Cicer arietinum L.) variety, Awarodhi, under Central Uttar Pradesh conditions in 2015 and 2016. The trial was laid out in factorial randomized block design with three replications. The experiment on the chickpea (Cicer arietinum L.) crop was conducted at Nawabganj Research Farm of Chandra Shekhar Azad University of Agriculture and Technology, Kanpur (U.P.) during Rabi season for year 2015-16, to assess the response of Rhizobium and PSB as affected by their application. The result shows that some plant attributes of the crop like the number of nodules varied from 8 to 25 at 30 days and 12 to 43 at 60 days. The yield of the crop was also varied from 12 to 26 qtl. ha of seeds of chickpea (Cicer arietinum L.) and 13.7 to 35.0 qtl. ha Stover of the crop. Maximum N and P uptake in grain and straw as well as protein content in grain were noted maximum with dual inoculation of (Rhizobiu...
Journal of Plant Nutrition, 2021
Abstract Deficiency and toxicity of micronutrient boron (B) play a critical role in plant product... more Abstract Deficiency and toxicity of micronutrient boron (B) play a critical role in plant productivity. In this study, the evaluation of B supplementation on biomass and essential oil (EO) yield of rose-scented geranium (Pelargonium graveolens L.) and its distribution at different application rates (2.5, 5.0, and 7.5 kg ha−1) was performed in a field trial during the growing season of two consecutive years 2017–18 and 2018–19. Boron uptake, plant biomass, and EO yield along with EO constituent in leaves were determined at different time scales. Application of B significantly improved the biomass yield of P. graveolens and at B-II treatment (5.0 kg ha−1 dose) highest biomass and EO yield was recorded, however, B-III treatment (7.5 kg ha−1) demonstrated toxicity symptoms like the decline in protein and chlorophyll content and an increase in proline and stress enzymes (SOD, CAT) in plant leaves. The effects of B on EO constituents varied with the different developmental stages of P. graveolens. Furthermore, the application of B at 5.0 kg ha−1 acts as a stimulant in upgrading the quality and quantity of EO with improved main aroma constituent’s P. graveolens than the control without modulating odor quality i.e., citronellol:geraniol (C:G) ratio. Hence, the study revealed a balanced level of B as a crucial parameter for the enhanced productivity with the improved economic return of P. graveolens.
Physical Review D, 2020
X-ray reflection spectroscopy is a promising technique for testing general relativity in the stro... more X-ray reflection spectroscopy is a promising technique for testing general relativity in the strong field regime, as it can be used to test the Kerr black hole hypothesis. In this context, the parametrically deformed black hole metrics proposed by Konoplya, Rezzolla & Zhidenko (Phys. Rev. D93, 064015, 2016) form an important class of non-Kerr black holes. We implement this class of black hole metrics in relxill nk, which is a framework we have developed for testing for non-Kerr black holes using X-ray reflection spectroscopy. We perform a qualitative analysis of the effect of the leading order strong-field deformation parameters on typical observables like the innermost stable circular orbits and the reflection spectra. We also present the first X-ray constraints on some of the deformation parameters of this metric, using Suzaku data from the supermassive black hole in Ark 564, and compare them with those obtained (or expected) from other observational techniques like gravitational waves and black hole imaging.
Optik, 2021
Abstract The prime theme of this work is to explore the excitation wavelength dependent photolumi... more Abstract The prime theme of this work is to explore the excitation wavelength dependent photoluminescence characteristics and white light generation in activators [europium (Eu) and terbium (Tb)] doped yttrium borate (YBO3) phosphors. In order to study the influence of excitation wavelength on photoluminescence emission intensity, a fixed amount (5 mol%) of Tb and different concentration of Eu (1, 2, 3, 5 and 7 mol%) were co-doped into yttrium borate (YBO3) host matrix via a solution precursor route using sodium borohydride as a precipitating agent. The ratio of Tb and Eu emission peaks suggests that it is possible to produce multi-color emissions including white light. The excitation dependence of emission comes from the combined contribution of host, activator and energy transfer between host to activator as well as among individual activators, which gives rise to change in output emission color. Moreover, the optimum composition i.e. 3 mol% Eu, 5 mol% Tb co-doped YBO3 was found to be appropriate for white light emitting phosphor.
Materials Chemistry and Physics, 2020
This work explores the effect of milling on morphology and PL of Eu-doped YBO 3. � Crystallite an... more This work explores the effect of milling on morphology and PL of Eu-doped YBO 3. � Crystallite and particle size of Eu-doped YBO 3 decreases with milling time. � Particles get ruptured and shattered to nanoscale range during milling. � Smaller particles with surface disorder due to milling causes an increase of R/ O. � Excitation wavelength of 254 nm suggests better CIE and samples are red in color.
Biofilms have significant role in microbial persistence, antibiotic resistance and chronic infect... more Biofilms have significant role in microbial persistence, antibiotic resistance and chronic infections; consequently, there is a pressing need for development of novel “anti-biofilm strategies”. One of the fundamental mechanisms involved in biofilm formation is protein-protein interactions of ‘amyloid like proteins’ (ALPs) in extracellular matrix. Such interactions could be potential targets for development of novel anti-biofilm strategies; therefore, assessing the structural features of these interactions could be of great scientific value. Characterization of biomolecular interaction with conventional structure biology tools including X-Ray diffraction and Nuclear Magnetic Resonance is technically challenging, expensive and time-consuming. In contrast, modelling such interactions is time-efficient, economical and might provide deeper understanding of structural basis of interactions. Therefore, during the present study, protein-protein interaction of TasA(28-261)–TapA(33-253) (whic...
Materials Today: Proceedings, 2018
In this paper, the effect of heat treatment and warmuni-axially compression of AA 2014 alloy were... more In this paper, the effect of heat treatment and warmuni-axially compression of AA 2014 alloy were studied at different amount of deformations. Microstructural characterization and mechanical properties were studied for deformed and precipitation hardened specimens. Differential scanning calorimetry test was performed to check thermal stability of specimen, and observed that thermal stability of precipitation hardened specimen is highest. Wear test was conducted with the help of pin on disc wear testing machine, and observed that wear rate was increased with increasing load, and also precipitation hardened and deformed specimens were more wear resistant as compared to as-received material.
Journal of Biomolecular Structure and Dynamics, 2019
Abstract Prolyl oligopeptidase (POP) enzyme has been studied for various disorders, viz. Schizoph... more Abstract Prolyl oligopeptidase (POP) enzyme has been studied for various disorders, viz. Schizophrenia, Alzheimer’s, Parkinson’s, Depression, Inflammation, etc., for three decades, but no drug has passed through the clinical trials, possibly because of indigent pharmacokinetics. This might have been a result of similar structures of drug candidates. This study aimed at identifying novel small non-peptidomimetic inhibitors for POP enzyme that could serve as a lead for developing newer drugs. Structure-based virtual screening of molecules of MolMall database was conducted on the POP enzyme (PDB ID 3DDU) to identify potential hits. The hits identified were subjected to computational pharmacokinetic screening followed by molecular mechanics/generalized Born and surface area studies to estimate the binding free energy of the docked complexes. After that, nine hits were selected and tested for POP inhibitory activity, among which one compound MM 4 was found to be most potent with EC50 of 100 µM. Compound MM 4 was further subjected to molecular dynamics simulations to study the overall stability of the ligand–protein complex. The compound interacted strongly with catalytic amino acid Arg643 by forming salt and water bridges; it also interacted well with amino acids Phe173, Arg252 and Met235. This study provides a lead molecule for further development of POP inhibitors. Communicated by Ramaswamy H. Sarma
International journal of biological macromolecules, Jan 9, 2018
Development of resistance against existing anti-epileptic drugs has alarmed the scientific innova... more Development of resistance against existing anti-epileptic drugs has alarmed the scientific innovators to find novel potential chemical starting points for the treatment of epilepsy and GABA inhibition is a promising drug target strategy against epilepsy. The crystal structure of a subtype-selective β3-homopentameric ligand-gated ion channel of GABA receptor has been used for the first time for screening the Asinex library for discovery of GABA agonists as potential anti-epileptic agents. Co-crystallized ligand established the involvement of part of the β7-β8 loop (Glu155 and Tyr157) and β9-β10 loop (Phe200 and Tyr205) residues as the crucial amino acids in effective binding, an essential feature, being hydrogen bond or ionic interaction with Glu155 residue. Top ranked hits were further subjected to binding energy estimation, ADMET analysis and ligand efficiency matric calculations as consecutive filters. About 19 compounds qualifying all parameters possessed interaction of one posit...
Journal of receptor and signal transduction research, Jan 31, 2017
Multidrug resistance along with side-effects of available anti-epileptic drugs and unavailability... more Multidrug resistance along with side-effects of available anti-epileptic drugs and unavailability of potent and effective agents in submicromolar quantities presents the biggest therapeutic challenges in anti-epileptic drug discovery. The molecular modeling techniques allow us to identify agents with novel structures to match the continuous urge for its discovery. KCNQ2 channel represents one of the validated targets for its therapy. The present study involves identification of newer anti-epileptic agents by means of a computer-aided drug design adaptive protocol involving both structure-based virtual screening of Asinex library using homology model of KCNQ2 and 3D-QSAR based virtual screening with docking analysis, followed by dG bind and ligand efficiency calculations with ADMET studies, of which 20 hits qualified all the criterions. The best ligands of both screenings with least potential for toxicity predicted computationally were then taken for molecular dynamic simulations. Al...
Materials science & engineering. C, Materials for biological applications, 2017
Bortezomib (BTZ) is the first proteasome inhibitor approved by the US-FDA is majorly used for the... more Bortezomib (BTZ) is the first proteasome inhibitor approved by the US-FDA is majorly used for the treatment of newly diagnosed and relapsed multiple myeloma including mantle cell lymphoma. BTZ is hydrophobic in nature and is a major cause for its minimal presence as marketed formulations. The present study reports the design, development and characterization of dendrimer based formulation for the improved solubility and effectivity of bortezomib. The study also equally focuses on the mechanistic elucidation of solubilization by two types of dendrimers i.e. fourth generation of poly (amidoamine) dendrimers (G4-PAMAM-NH2) and fifth generation of poly (propylene) imine dendrimers (G5-PPI-NH2). It was observed that aqueous solubility of BTZ was concentration and pH dependent. At 2mM G5-PPI-NH2 concentration, the fold increase in bortezomib solubility was 1152.63 times in water, while approximately 3426.69 folds increase in solubility was observed at pH10.0, respectively (p<0.05). The...
Journal of Biomolecular Structure and Dynamics, 2016
Structure-based screening approach targeting mGlu2 receptor was carried out to identify good chem... more Structure-based screening approach targeting mGlu2 receptor was carried out to identify good chemical starting points for anti-epileptic therapy. Interactive modes of final 12 compounds identified on the basis of screening of Asinex library, binding energy analysis, ADME profiling with special emphasis for CNS ranges, and toxicity analysis were studied and showed good binding modes in the mGluR2-active site. Enrichment studies for validating screening protocol were carried out which gave ROC values 0.98 (AUC = 0.96) for SP, 0.97 (AUC = 0.95) for XP with BEDROC analysis. Our results indicate that all the 12 hits showed good CNS drug-like properties, have better binding free energy and ADME profile as compared to co-crystallized ligand with the best ligand hit retaining conserved hydrogen bond interactions with Ala-166, Thr-168, Ser-145, and Arg-61 residues in bilobatevenus fly-trap domain of mGluR2 receptor. Molecular dynamics simulations proved that the two potential hits, qualifying all screening parameters, are stable in the receptor active site pocket, confirming the potential of the identified hits as a specific target for mGluR2. Because the newly discovered mGluR2 agonists are structurally different with Tc values ranging from 0.57 to 0.92, all of them can be considered for further de novo design methods.
Journal of receptor and signal transduction research, Jan 8, 2016
Biological mechanism attributing mutations in KCNQ2/Q3 results in benign familial neonatal epilep... more Biological mechanism attributing mutations in KCNQ2/Q3 results in benign familial neonatal epilepsy (BFNE), a rare form of epilepsy and thus neglected. It offers a potential target for antiepileptic drug discovery. In the present work, a pharmacophore-based 3D-QSAR model was generated for a series of N-pyridyl and pyrimidine benzamides possessing KCNQ2/Q3 opening activity. The pharmacophore model generated contains one hydrogen bond donor (D), one hydrophobic (H), and two aromatic rings (R). They are the crucial molecular write-up detailing predicted binding efficacy of high affinity and low affinity ligands for KCNQ2/Q3 opening activity. Furthermore, it has been validated by using a biological correlation between pharmacophore hypothesis-based 3D-QSAR variables and functional fingerprints of openers responsible for the receptor binding and also by docking of these benzamides into the validated homology model. Excellent statistical computational tools of QSAR model such as good corr...
Journal of Molecular Structure, 2016
High throughput virtual screening and in-silico ADMET analysis for rapid and efficient identifica... more High throughput virtual screening and in-silico ADMET analysis for rapid and efficient identification of potential PAP 248-286 aggregation inhibitors as anti-HIV agents.
Journal of Biomolecular Structure and Dynamics, 2016
Malaria is an endemic disease caused by the protozoan parasite Plasomodium falciparum. Febrifugin... more Malaria is an endemic disease caused by the protozoan parasite Plasomodium falciparum. Febrifugine analogues are natural compound obtained from the traditional Chinese herbs have shown significant antimalarial and anticancerous efficacy in experimental model. Development of resistance against the existing antimalarial drug has alarmed the scientific innovators to find a potential antimalarial molecule which can be further used by endemic countries for the elimination of this disease. In this study, structure-based virtual screening and molecular dynamics (MD) base approaches were used to generate potential antimalarial compound against plasmepsin II and prolyl-tRNA synthetase of Plasmodium. Here, we have docked series of febrifugine analogues (n = 11,395) against plasmepsin II in three different docking modes and then it was compared with previously reported target prolyl-tRNA synthetase. Extra precision docking resulted into 235 ligands having better docking score were subject for QikProp analysis. Better ligands (n = 39) obtained from QikProp analysis were subject for ADMET prediction and docking protocol validation through the estimation of receiver operator characteristics. In the later stage, 24 ligands obtained from ADMET study were subject for the estimation of binding energy through MM-GBSA and same were also docked against prolyl-tRNA synthetase to get compounds with dual inhibitor role. Finally, MD simulation and 2D fingerprint MACCS study of two best ligands have shown significant interaction with plasmepsin II and homology against known active ligand with noteworthy MACCS index, respectively. This study concludes that FA12 could be potential drug candidate to fight against Plasmodium falciparum parasites.
International Journal of Research, May 14, 2015
This paper discusses the background and application requirements that motivated the development o... more This paper discusses the background and application requirements that motivated the development of TinyOS. It enumerates the characteristics associated with any typical Networked sensor application. Technological progress in integrated, low-power, CMOS communication devices and sensors makes a rich design space of networked sensors viable.
Proceedings of the Industrial Track of the 16th International Middleware Conference, 2015
Online commerce platforms connect suppliers to customers using internet. In online travel industr... more Online commerce platforms connect suppliers to customers using internet. In online travel industry, the suppliers provide a programmatic interface for the platform to query and book travel services. Typically, multiple competitive platforms connect to the same set of suppliers and any change in inventory level leads to changes in availability and pricing. One of the key problems that online platforms deal with is to ensure the accuracy of inventory availability and pricing, while ensuring low response time to the customers. In this work, we present the design and implementation of DynaCorrect, a dynamically correcting cache for non-cooperative systems. DynaCorrect caches inventory data from remote suppliers to ensure low response time. Since the inventory price and availability may change in the background, DynaCorrect employs random sampling and a feedback loop to correct the cache. Further, in order to ensure high cache hit rate, it refreshes inventory based on popularity, spatial and temporal locality. Finally, it employs deduplication to ensure high resource efficiency for the caching system. We implemented DynaCorrect in production over a period of time and observed significant benefits to achieve the goals of high accuracy, low response time and reduced number of queries to the suppliers.