67 results on '"Dey, D."'
Search Results
2. In silico Studies Predict Efficient Binding of Remdesivir and Favipiravir with 3-chymotrypsin like protease of SARS-CoV-2 for COVID-19 Interventional Therapy.
- Author
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DEY, D., DEY, N., GHOSH, SHALINI, and THIAGARAJAN, PADMA
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COVID-19 treatment , *COVID-19 , *RNA polymerases , *SARS-CoV-2 , *REMDESIVIR , *VIRUS-induced enzymes , *HYDROPHOBIC interactions - Abstract
Favipiravir and remdesivir are investigational drugs for coronavirus disease 2019 that is caused by severe acute respiratory syndrome coronavirus 2. The active forms of these drugs are reported to target and inhibit viral RNA dependent RNA polymerase, which is derived from 3-chymotrypsin like protease, a viral replicase enzyme. The present in silico study explores the comparative efficacy of these drugs to inhibit 3-chymotrypsin like protease and RNA dependent RNA polymerase, to plan therapeutic options for patients based on their disease severity. Active favipiravir and remdesivir molecules bind to 3-chymotrypsin like protease with energies of 6.18 and -6.52 kcal/mol in contrast to -5.62 and -3.91 kcal/mol for RNA dependent RNA polymerase. Further, hydrophobic interactions and salt bridge formations cement drug bindings with 3-chymotrypsin like protease, but not with RNA dependent RNA polymerase. Molecular dynamic simulation experiments, performed under certain experimental constraints reveal that the root mean square flexibilities of active residues in drug complexes with 3-chymotrypsin like protease are lower than in free 3-chymotrypsin like protease making the former more stable than the latter because of their rigidity and stabilities. Both drugs may hence serve as good therapeutic options for early stages of coronavirus disease 2019. However, more severe symptoms may be treated better with favipiravir due to its better binding with RNA dependent RNA polymerase, as compared to remdesivir. The "one drug does not fit all" concept is true for coronavirus disease 2019 as it is being currently realized by clinicians all around the world. Hence precise knowledge about critical interactions of these drugs with the viral enzymes will help medicos make vital therapeutic decisions on interventional options for patients who report to hospitals without over symptoms or with varying degrees of disease severity. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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3. 81 Basis for aminoglycoside evasion of bacterial antibiotic resistance arising from ribosomal RNA modification.
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Dey, D., Mattingly, J., Zelinskaya, N., Dunham, C., and Conn, G.
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RNA modification & restriction , *RIBOSOMAL RNA , *DRUG resistance in bacteria - Published
- 2023
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4. A deep learning framework using convolution neural network for classification of impulse fault patterns in transformers with increased accuracy.
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Dey, D., Chatterjee, B., Dalai, S., Munshi, S., and Chakravorti, S.
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ELECTRIC fault location , *ARTIFICIAL neural networks , *DEEP learning , *ELECTRIC windings , *ELECTRIC transformers , *FAULT currents - Abstract
The paper presents a method using deep learning framework based on convolution neural network (CNN), for identification and localization of faults of transformer winding under impulse test. The results show that the proposed method outperforms the existing methods significantly. The present scheme eliminates the requirement of separate feature extraction and classification algorithms for the analysis of fault current patterns. A part of the proposed network performs feature learning and the other part classifies the features in a supervised manner. The method is computation intensive but capable of achieving very high degree of accuracy; on an average a margin of more than 7% compared to other published literature till date. [ABSTRACT FROM AUTHOR]
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- 2017
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5. Effect of planting dates and botanical insecticides against major Lepidopterous pests of cabbage: A review.
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Dey, D., Routray, S., Baral, S., and Mahantheshwara, B.
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PLANTING , *BOTANICAL insecticides , *CABBAGE diseases & pests , *GERMINATION , *LARGE white (Insect) - Abstract
Cabbage (Brassicae oleracea var. capitata Linn.) is one of the most important and extensively cultivated vegetable crop because of its nutritional and economical values for producers and consumer point of view, respectively. The crop is prone for infestation by a number of insect pests consisting sucking and defoliating insects starting from germination to harvesting stage of the crop. In India, the diamond back moth, Plutella xylostella Linneaus and cabbage butterfly, Pieris brassicae Linneaus are the major Lepidopterous pests of cabbage. Adjusting planting dates can sometimes help to avoid certain insect infestations and reduce the need for chemical control. Planting dates influence the crop performance due to changed biotic and abiotic factors. The time of planting of cabbage, which is a season bound crop, has profound effect on the incidence of diamond back moth and cabbage butterfly. Several insecticides have been recommended through ages to avert pest damage, but some broad-spectrum synthetic organic insecticides and biopesticides are effective for the control of these two Lepidopterous pests. [ABSTRACT FROM AUTHOR]
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- 2017
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6. Genetic improvement of natural enemies: A review.
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Routray, S., Dey, D., Baral, S., Das, A. P., and Mahantheshwara, B.
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PHYSIOLOGICAL control systems , *CONTROL of agricultural pests & diseases , *PROGENY tests (Botany) , *RECOMBINANT DNA , *PLANT selection , *CROP genetics - Abstract
Biological control has been accepted as an eco-friendly, technically appropriate, economically viable and socially acceptable method of pest management. Various technologies and methods have been adapted in order to genetically improve the performances of natural enemies (predators, parasitoids and pathogens). Artificial selection of various strains under different conditions, hybridization (heterosis) of different strains and rDNA technologies has been adopted towards these directions. Various traits like tolerant to pesticidal stress, tolerant to extreme abiotic stresses, shortening developmental rate, enhancing progeny production, altering sex ratio and altering host or habitat preferences could enhance the effectiveness of natural enemies. The genetically improved natural enemies (predators, parasitoids and pathogens) might be the next level biological weapons against the pest populations in agricultural systems. [ABSTRACT FROM AUTHOR]
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- 2016
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7. Cross-spectrum analysis based methodology for discrimination and localization of partial discharge sources using acoustic sensors.
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Biswas, S., Dey, D., Chatterjee, B., and Chakravorti, S.
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PARTIAL discharges , *ACOUSTIC transducers , *ELECTRIC transformers , *WAVELET transforms , *ACOUSTIC emission - Abstract
In this paper, a scheme has been developed for detecting individual, as well as multiple partial discharge (PD) sources within a transformer tank through acoustic sensors. For that purpose, in the laboratory, a transformer tank has been emulated inside which, provisions are made to place artificially created partial discharge sources at different locations. An experimental setup has been prepared to record the acoustic PD signal through multiple acoustic sensors placed at the outside surfaces of the walls. Presented results show the signature of the acquired data pattern for both individual and multiple discharges. Acoustic PD detection method experiences difficulty in locating the PD source accurately due to interference or attenuation of signals from the environmental noise. It is seen that Cross-wavelet transform (XWT) has an ability to nullify the effect of random noises present in the acquired acoustic PD signal. Thus, cross-wavelet transform based feature extraction with ensemble binary support vector machine based classifier is used for locating the partial discharge sources within the tank. These methodologies have been chosen as they suit well to discriminate between the PD sources at different locations inside the tank. Results indicate that the average classification accuracy is 92.8%. The contribution of this research work is in discriminating individual as well as multiple partial discharge sources which produce acoustic emission simultaneously. Experimental results indicate that the proposed methodology can be used to localize partial discharge sources in high voltage apparatus where the acoustic signals due to partial discharges find a path to propagate towards the outer surface. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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8. 517 Validation of the 'Goldilocks binding affinity' hypothesis for aminoglycoside recognition in the Pseudomonas aeruginosa efflux transporter MexY.
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Kavanaugh, L., Dey, D., and Conn, G.
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PSEUDOMONAS aeruginosa , *HYPOTHESIS - Published
- 2022
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9. Managed realignment for habitat compensation: Use of a new intertidal habitat by fishes.
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Nunn, A.D., Clifton-Dey, D., and Cowx, I.G.
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INTERTIDAL fishes , *TIDAL flats , *FISH habitats , *FISH diversity , *FISH ecology - Abstract
Managed realignment has become an increasingly common mechanism to increase the efficiency and sustainability of flood defences, reduce defence costs or compensate for habitat losses. This study investigated the use by fishes of a new intertidal habitat, created by managed realignment, intended to compensate for the loss of mudflat associated with a major port development. Although broadly similar, statistically significant differences in fish species composition, abundance, biomass, size structure, diversity and diet composition indicate that the managed realignment is not yet functioning in an identical manner to the mudflat in the adjacent estuary, most likely due to differences in habitat between sites. Notwithstanding, similarity in the species composition of fyke catches in the managed realignment and estuary increased annually during the 5-year study period, suggesting that the mudflat in the realignment is still developing. Indeed, the site will inevitably change over time with accretion, establishment of vegetation and possibly development of creeks. This will not necessarily prevent the aim of the realignment scheme being achieved, as long as sufficient suitable mudflat remains. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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10. Cancer complicating systemic lupus erythematosus – a dichotomy emerging from a nested case-control study.
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Dey, D, Kenu, E, and Isenberg, DA
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CANCER risk factors research , *SYSTEMIC lupus erythematosus , *RETROSPECTIVE studies , *ENZYME-linked immunosorbent assay , *UNIVARIATE analysis , *MEDICAL records , *PATIENTS - Abstract
The article presents a study which examined the levels of individual cancer risks in systemic lupus erythematosus (SLE) patients. It states that the study conducted a retrospective review of the cancer patients' medical records. It cites various procedures undertaken in the study such as enzyme-linked immunosorbent assay (ELISA), univariate analysis, and laser nephelometry. It concludes that serological and clinical factors contribute to the increased malignancy in SLE risk.
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- 2013
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11. APPROXIMATE FIXED POINT OF REICH OPERATOR.
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DEY, D. and SAHA, M.
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FIXED point theory , *OPERATOR theory , *APPROXIMATION theory , *DIAMETER , *MATHEMATICAL models , *METRIC spaces - Abstract
In the present paper, we study the existence of approximate fixed point for Reich operator together with the property that the ϵ-fixed points are concentrated in a set with the diameter tends to zero if ϵ → 0. [ABSTRACT FROM AUTHOR]
- Published
- 2013
12. An ensemble system for automatic sleep stage classification using single channel EEG signal.
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Koley, B. and Dey, D.
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SLEEP stages , *ELECTROENCEPHALOGRAPHY , *SLOW wave sleep , *SLEEP-wake cycle , *PATTERN recognition systems , *SUPPORT vector machines - Abstract
The present work aims at automatic identification of various sleep stages like, sleep stages 1, 2, slow wave sleep (sleep stages 3 and 4), REM sleep and wakefulness from single channel EEG signal. Automatic scoring of sleep stages was performed with the help of pattern recognition technique which involves feature extraction, selection and finally classification. Total 39 numbers of features from time domain, frequency domain and from non-linear analysis were extracted. After extraction of features, SVM based recursive feature elimination (RFE) technique was used to find the optimum number of feature subset which can provide significant classification performance with reduced number of features for the five different sleep stages. Finally for classification, binary SVMs were combined with one-against-all (OAA) strategy. Careful extraction and selection of optimum feature subset helped to reduce the classification error to 8.9% for training dataset, validated by k-fold cross-validation (CV) technique and 10.61% in the case of independent testing dataset. Agreement of the estimated sleep stages with those obtained by expert scoring for all sleep stages of training dataset was 0.877 and for independent testing dataset it was 0.8572. The proposed ensemble SVM-based method could be used as an efficient and cost-effective method for sleep staging with the advantage of reducing stress and burden imposed on subjects. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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13. Factors Impacting Rhizobium-legume Symbiotic Nitrogen Fixation with the Physiological and Genetic Responses to Overcome the Adverse Conditions: A Review.
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Owaresat, J. K., Siam, M. A. Habib, Dey, D., Jabed, S., Badsha, F., Islam, M. R., and Kabir, M. S.
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LEGUMES , *ROOT-tubercles , *NITROGEN fixation , *HEAT shock proteins , *DENATURATION of proteins , *GENETIC engineering , *NITROGEN compounds - Abstract
Symbiotic N2 fixation is essential for the plant's growth because it can fix reactive nitrogen compounds in soil. However, all steps of this process can be hampered by several biotic and abiotic environmental factors. This study mainly focused on discussing the impacts of 12 major factors on this process by reviewing the significant numbers of research works. According to the information from these works, we found some significant physiological and genetic impacts caused by these factors like plasmid deletion, genomic mismanagement, abnormal molecular signals, toxicity, deficiency of minerals, deformation of rhizobial cells, protein denaturation, nucleic acid damage, acetylene reduction and nod factors limitation. Furthermore, expression of heat or acid shock proteins, internal buffering, genes spanning, extracellular immobilization, periplasmic allocation, change of lipopolysaccharides composition, intracellular accumulation of inorganic and organic solutes (Osmolyte) and activation of hydrogenase expression are shown by both micro and macro symbionts as a natural response to adapt to these stress conditions. Though the stress-tolerant strains like HR-3, HR-6, HR-10, HR-12, acta, actP, exoR, lpiA, actR, actS and phrR can be used to sense the external environment and make signals to change gene transcription during the adverse condition, the application of genetic engineering should be expanded more to promote the commercial inoculation by the production of novel stress-tolerant strains or modified genes of rhizobia and legumes. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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14. Bilateral fungiform papilloma with synchronous verrucous carcinoma of the nasal septum: a rare presentation and a literature review.
- Author
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Maithani, T, Dey, D, Pandey, A, and Chawla, N
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HEALTH outcome assessment , *NASAL tumors , *PAPILLOMA , *TOMOGRAPHY , *COMORBIDITY , *TREATMENT effectiveness , *SYMPTOMS , *DIAGNOSIS - Abstract
Aim:Fungiform papillomas are benign mucosal neoplasms presenting as a unilateral exophytic mass involving the anterior portion of the nasal septum. In this study, we present an exceptional case of a bilateral fungiform papilloma with a synchronous verrucous carcinoma of the nasal septum.Material and methods:A case study with a review of the literature concerning malignant changes in fungiform papilloma.Results:The general consensus in most of the literature is that malignant change in fungiform papilloma is exceptional. Our patient is probably the third reported case of verrucous carcinoma of the nasal septum, and the first report of a bilateral fungiform papilloma with a synchronous verrucous carcinoma. The tumour was subjected to complete surgical removal in the first instance. There was no recurrence at follow up seven months after surgery.Conclusion:Although fungiform papillomas are generally not premalignant, occasional malignant transformation may occur. Thus, they must be managed with the utmost cautiousness. [ABSTRACT FROM PUBLISHER]
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- 2012
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15. LAYER-BY-LAYER SELF-ASSEMBLED FILMS OF ROSE BENGAL.
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HUSSAIN, S. A., DEY, D., and BHATTACHARJEE, D.
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MULTILAYERED thin films , *MOLECULAR self-assembly , *ROSE bengal , *ADSORPTION (Chemistry) , *ELECTROPHORETIC deposition , *MICROGRAPHICS , *ABSORPTION spectra - Abstract
Layer-by-Layer (LBL) self-assembled films of rose bengal (RB) have been fabricated onto quartz substrate by the alternative adsorption of polycation poly (amine hydrochloride) (PAH) and RB. UV-Vis absorption studies reveal the formation of RB dimmer in PAH-RB LbL films. Scanning Electron Micrograph (SEM) picture confirms the aggregation of RB molecules in LbL films. Almost 15 min is required to complete the interaction between RB and PAH molecules in the 1 bilayer LbL film. The dye (RB) was found to come off the film during the subsequent poly cation (PAH) deposition. As an alternative approach RB was anchored to the polycation PAH via physiadsorption and controlling the concentration of the combination of RB and PAH was used as polycation and poly (acrylic acid) (PAA) as polyanion for film deposition. The absorption spectra after each deposition showed that there was no material loss during layer depositions via second method. [ABSTRACT FROM AUTHOR]
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- 2011
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16. MOLECULAR SELF-ASSEMBLY OF CHICAGO SKY BLUE ONTO SOLID SUBSTRATE.
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ISLAM, MD. N., DEY, D., BHATTACHARJEE, D., and HUSSAIN, SYED ARSHAD
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MOLECULAR self-assembly , *SUBSTRATES (Materials science) , *ADSORPTION (Chemistry) , *THIN films , *SCANNING electron microscopy , *FOURIER transform infrared spectroscopy , *ELECTROSTATICS , *NANOCRYSTALS - Abstract
Self-assembled films of organic dye Chicago Sky Blue 6B (CSB) have been fabricated onto solid substrate by electrostatic alternate adsorption of polycation ploy(allylamine hydrochloride) (PAH) and CSB. UV-Vis absorption spectroscopic studies reveal the successful incorporation of CSB molecules into Layer-by-Layer (LbL) films and consequent formation of aggregates. This view is supported by FTIR spectroscopic studies. Scanning electron microscope picture confirms the formation of nanocrystalline aggregates in the LbL films. About 15 min is required to complete the electrostatic interaction between PAH and CSB molecules in one bilayer LbL film. [ABSTRACT FROM AUTHOR]
- Published
- 2011
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17. Optical Biosensors: A Revolution Towards Quantum Nanoscale Electronics Device Fabrication.
- Author
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Dey, D. and Goswami, T.
- Abstract
The dimension of biomolecules is of few nanometers, so the biomolecular devices ought to be of that range so a better understanding about the performance of the electronic biomolecular devices can be obtained at nanoscale. Development of optical biomolecular device is a newmove towards revolution of nano-bioelectronics. Optical biosensor is one of such nano-biomolecular devices that has a potential to pave a new dimension of research and device fabrication in the field of optical and biomedical fields. This paper is a very small report about optical biosensor and its development and importance in various fields. [ABSTRACT FROM AUTHOR]
- Published
- 2011
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18. Classification of dynamic insulation failures in transformer winding during impulse test using cross-wavelet transform aided foraging algorithm.
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Rajamani, P., Dey, D., and Chakravorti, S.
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ELECTRIC insulators & insulation , *FAILURE analysis , *ELECTRIC transformers , *WAVELETS (Mathematics) , *ALGORITHMS , *SIMULATION methods & models - Abstract
Bacterial foraging-based approach for identification of fault characteristics of dynamic insulation failure in transformer during impulse test has been proposed. The winding currents acquired by tank current method during impulse test are analysed for identification of fault characteristics. The time-frequency domain-based features extracted from cross-wavelet spectra of winding currents of insulation failed and no-fault (healthy) insulation of transformer are given as input to the foraging algorithm for identification of dynamic insulation failure characteristics. The required winding currents to extract the significant features are acquired by emulating different dynamic insulation failures in the developed analogue model of 33 kV winding of 3 MVA transformer. To emulate various fault characteristics in analogue model, suitable fault emulator modules have been developed. Results show that the proposed foraging algorithm with cross-wavelet transform features could successfully identify the fault characteristics of dynamic insulation failure with acceptable accuracy. The classification accuracy of proposed foraging algorithm is also compared with fuzzy c-means classification algorithm. The concepts of dynamic arc model simulation, cross-wavelet transform feature extraction, emulation of dynamic insulation failure in analogue model of transformer and fault characteristics identification are explained. [ABSTRACT FROM AUTHOR]
- Published
- 2010
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19. Cross-wavelet Transform as a New Paradigm for Feature Extraction from Noisy Partial Discharge Pulses.
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Dey, D., Chatterjee, B., Chakravorti, S., and Munshi, S.
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ELECTRIC discharges , *WAVELETS (Mathematics) , *ELECTROMAGNETIC noise , *SET theory , *ARTIFICIAL neural networks , *ELECTRIC insulators & insulation - Abstract
In this work a new approach based on cross-wavelet transform towards identification of noisy Partial Discharge (PD) patterns has been proposed. Different partial discharge patterns are recorded from the various samples prepared with known defects. A novel cross-wavelet transform based technique is used for feature extraction from raw noisy partial discharge signals. Noise is a significant problem in PD detection. The proposed method eliminates the requirement of denoising prior to processing and therefore it can be used to develop an automated and intelligent PD detector that requires minimal human expertise during its operation and analysis. A rough-set theory (RST) based classifier is used to classify the extracted features. Results show that the partial discharge patterns can be classified properly from the noisy waveforms. The effectiveness of the feature extraction methodology has also been verified with two other commonly used classification techniques: Artificial Neural Network (ANN) based classifier and Fuzzy classifier. It is found that the type of defect within insulation can be classified efficiently with the features extracted from cross-wavelet spectra of PD waveforms by all of these methods with a reasonable degree of accuracy. [ABSTRACT FROM AUTHOR]
- Published
- 2010
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20. Rough-granular Approach for Impulse Fault Classification of Transformers using Cross-wavelet Transform.
- Author
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Dey, D., Chatterjee, B., Chakravorti, S., and Munshi, S.
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ELECTRIC transformers , *ELECTRIC currents , *WAVELETS (Mathematics) , *MATHEMATICAL models , *SET theory - Abstract
A novel approach based on information granulation using Rough sets for impulse fault identification of transformers has been proposed. It is found that the location and type of fault within a transformer winding can be classified efficiently by the features extracted from cross-wavelet spectra of current waveforms, obtained from impulse test. Results show that the proposed methodology can localize the fault within 5% of the winding length with a high degree of accuracy. The basic concepts of feature extraction using cross-wavelet transform and the method of classification of those features by rough-granular method are also explained. [ABSTRACT FROM AUTHOR]
- Published
- 2008
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21. A unified modeling framework for metabonomic profile development and covariate selection for acute trauma subjects.
- Author
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Ghosh, S. and Dey, D. K.
- Abstract
Acute trauma is often associated with progressive deterioration of multiple organ systems in humans and is the leading cause of death in trauma care units. Identification of specific organ failure in a non-invasive manner and the contribution of different demographic factors on the casual progression of acute trauma are of supreme interests for successful diagnosis, prognosis or monitoring of trauma status. Recently, electrospray ionization and matrix-assisted laser desorption time-of-flight mass spectrometry have been used to identify biomarkers in both proteomics and metabonomics studies. Data sets generated from mass spectrometers in such studies are generally very large in size and thus require the use of sophisticated statistical techniques to glean useful information. In a recent development, Ghosh et al. ( BMC Bioinformatics 2008; 9:38) suggested a unified semiparametric approach to distinguish urinary metabolic profiles in a group of traumatic subjects from those of a control group consisting of normal individuals. In this study we have extended their approach by combining available covariate information in the development of metabonomic profile of acute trauma. We have shown that age is a statistically significant covariate across trauma and control group, thus pointing out the fact that prognosis of trauma may be acutely linked with subjects' age. Copyright © 2008 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]
- Published
- 2008
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22. Photophysical characterization of layer-by-layer self-assembled films of deoxyribonucleic acid.
- Author
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Dey, D., Islam, M. N., Hussain, S. A., and Bhattacharjee, D.
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DNA , *IMMOBILIZED cells , *ELECTROSTATICS , *TEMPERATURE , *SPECTRUM analysis - Abstract
This communication reports the photophysical characterization of self-assembled layer-by-layer (LbL) films of DNA (deoxyribonucleic acid) fabricated at different temperatures by electrostatic interaction with a polycation, poly(allylamine hydrochloride). It was observed that there was a successful incorporation of DNA molecules in DNA{PAH LbL films at room temperature as well as after melting temperature. An abrupt increase in intensity was observed in the absorption spectra of the films fabricated at high temperature which is an indication of the immobilization of unzipped DNA after melting of DNA. The films were observed to remain unaffected even after 250 h of film fabrication. The total electrostatic interaction time between DNA and PAH is about 15 min, that is, no PAH binding site is free. [ABSTRACT FROM AUTHOR]
- Published
- 2008
23. Preparation and characterization of an anionic dye–polycation molecular films by electrostatic layer-by-layer adsorption process
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Dey, D., Hussain, S.A., Nath, R.K., and Bhattacharjee, D.
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MOLECULAR weights , *DYES & dyeing , *AMARANTHS , *ADSORPTION (Chemistry) , *MOLECULAR spectroscopy , *NUCLEAR excitation - Abstract
Abstract: This communication reports the formation and characterization of self-assembled films of a low molecular weight anionic dye amaranth and polycation poly(allylamine hydrochloride) (PAH) by electrostatic alternating layer-by-layer (LBL) adsorption. It was observed that there was almost no material loss occurred during adsorption process. The UV–vis absorption and fluorescence spectra of amaranth solution reveal that with the increase in amaranth concentration in solution, the aggregated species starts to dominate over the monomeric species. New aggregated band at 600nm was observed in amaranth–PAH mixture solution absorption spectrum. A new broad low intense band at the longer wavelength region, in the amaranth–PAH mixture solution fluorescence spectrum was observed due to the closer association of amaranth molecule while tagged into the polymer backbone of PAH and consequent formation of aggregates. The broad band system in the 650–750nm region in the fluorescence spectra of different layered LBL films changes in intensity distribution among various bands within itself, with changing layer number and at 10 bilayer LBL films the longer wavelength band at 710nm becomes prominent. Existence of dimeric or higher order n-meric species in the LBL films was confirmed by excitation spectroscopic studies. Almost 45min was required to complete the interaction between amaranth and PAH molecules in the one-bilayer LBL film. [Copyright &y& Elsevier]
- Published
- 2008
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24. A Hybrid Filtering Scheme for Proper Denoising of Real-time Data in Dielectric Spectroscopy.
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Dey, D., Chatterjee, B., Chakravorti, S., and Munshi, S.
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DIELECTRICS , *ELECTRIC insulators & insulation , *BROADBAND dielectric spectroscopy , *SPECTRUM analysis , *ELECTRIC power production , *HYBRID power systems - Abstract
Condition monitoring of different power equipment with noninvasive and nondestructive techniques, such as Dielectric Spectroscopy, has become one of the important facets of power system reliability. This is increasingly becoming essential for predicting the insulation condition and probable future failure of power apparatus. Noise contamination, being one of the major problems in these measurements, should be treated judiciously. The paper proposes a simple but versatile real-time denoising scheme for this kind of signals of Dielectric spectroscopy in time domain namely, Polarization-Depolarization Current (PDC) and Recovery Voltage (RV), through a hybrid filtering technique using weighted median (WM) filter along with low pass digital infinite impulse response (IIR) filter. The proposed filter is able to remove real- life, random, high frequency noises as well as spurious impulse signals while preserving any step change in the signal. The performance of the proposed scheme is judged through experimentation using a real-time, automated computer controlled test setup for condition monitoring of transformers and the results show that it performs efficiently on different types of signals of dielectric spectroscopy in time domain, namely, PDC and RV. [ABSTRACT FROM AUTHOR]
- Published
- 2007
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25. A quantitative study of the morphological development and bacterial colonisation of the gut of the tammar wallaby Macropus eugenii eugenii and brushtail possum Trichosurus vulpecula during in-pouch development.
- Author
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Lentle, R. G., Dey, D., Hulls, C., Mellor, D. J., Moughan, P. J., Stafford, K. J., and Nicholas, K.
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TRICHOSURUS vulpecula , *NAIL-tailed wallabies , *INDIGESTION , *MARSUPIALS , *BODY weight , *ANIMAL culture - Abstract
We compared the rates of change of various morphological parameters of the stomach, small intestine, caecum and colon of tammar wallabies and brushtail possums with body mass during in-pouch development. These were correlated with changes in the numbers of bacterial species in the various gut segments. In the pouch-young of both species, the wet tissue masses of all gut segments increased with body mass in a positively allometric manner (i.e. with a body mass exponent > 1), suggesting that the mass of each component was disproportionately low at birth, but increased disproportionately rapidly postnatally. However, the lengths of the wallaby stomach and small intestine scaled isometrically with respect to body mass (i.e. with a body mass exponent around 0.33), which may indicate that the shape of these components changes to the adult form during early neonatal development. Conversely, the length of the caecum and colon of both wallabies and possums scaled in a positively allometric manner with respect to body mass, showing area to volume compensation. This may indicate a more general pattern of disproportionately rapid postnatal enlargement in areas that are distal to the principal sites of neonatal digestion (i.e. the stomach). The numbers of bacterial species present in the various gastrointestinal segments of both species were low in animals aged 100 days or less but there was a significant increase in microbial diversity in the caecum of brushtail possums aged over 100 days. The possum caecum also showed the greatest rate of increase in wet tissue mass relative to body mass. It is postulated that caecal development may act as a nidus for establishment of communities of commensal microflora in the developing marsupial. [ABSTRACT FROM AUTHOR]
- Published
- 2006
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26. Obesity in 70-year-old Swedes: Secular changes over 30 years.
- Author
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Eiben, G, Dey, D K, Rothenberg, E, Steen, B, Björkelund, C, Bengtsson, C, and Lissner, L
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OBESITY , *SWEDES , *MIDDLE-aged persons , *GERONTOLOGY , *EPIDEMICS , *PHYSICAL fitness - Abstract
OBJECTIVE:Secular increases in obesity have been widely reported in middle-aged adults, but less is known about such trends among the elderly. The primary purpose of this paper is to document the most recent wave of the obesity epidemic in population-based samples of 70-y-old men and women from Göteborg. Additionally, we will investigate the influences of physical activity, smoking and education on these secular trends.POPULATIONS AND METHODS:Five population-based samples of 3702 70-y-olds (1669 men and 2033 women) in Göteborg, Sweden, born between 1901 and 1930, were examined in the Gerontological and Geriatric Population Studies (H70) between 1971 and 2000. Cohort differences in anthropometric measures were the main outcomes studied. Physical activity, smoking habits and education were assessed by comparable methods in all cohorts. Subsamples of the women in the latest two cohorts (birth years 1922 and 1930) were also part of the Prospective Population Study of Women in Göteborg. In these women, it was possible to examine body mass index (BMI) and waist-to-hip circumference ratio (WHR) longitudinally since 1968.RESULTS AND CONCLUSIONS:Significant upward trends were found for height, weight, BMI, waist circumference (WC), WHR, prevalence of overweight (BMI≥25 kg/m2) and obesity (BMI≥30 kg/m2) across cohorts in both sexes. In 2000, 20% of the 70-y-old men born in 1930 were obese, and the largest increment (almost doubling) had occurred between the early 1980s and the early 1990s. In 70-y-old women the prevalence of obesity was 24% in 2000, a 50% increase compared to the cohort born 8 y earlier. BMI increased over time in all physical activity, smoking and education groups, with the exception of never-smoking men. Although 70-y-old women in 2000 were heavier than cohorts examined 8 y previously, data from the women studied longitudinally revealed that these differences were already present in earlier adulthood. In conclusion, the elderly population is very much part of the obesity epidemic, although secular trends in BMI were detected slightly earlier in men than in women. The health implications of these secular trends should be focused on in future gerontological research.International Journal of Obesity (2005) 29, 810–817. doi:10.1038/sj.ijo.0802940 Published online 3 May 2005 [ABSTRACT FROM AUTHOR]
- Published
- 2005
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27. Body composition estimated by bioelectrical impedance in the Swedish elderly. Development of population-based prediction equation and reference values of fat-free mass and body fat for 70- and 75-y olds.
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Dey, D K, Bosaeus, I, Lissner, L, and Steen, B
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LOW-fat diet , *BIOELECTRIC impedance , *HUMAN body composition - Abstract
Objective: To develop a bioelectrical impedance (BIA) prediction equation for fat-free mass (FFM[SUBBIA]) and present reference values of FFM and body fat (BF) for healthy Swedish elderly from population-based representative samples. Subjects: This study is based on 823 (344 males, 479 females) participants from two systematic samples of birth cohorts in Göteborg aged 70 (cohort H70V, 201 males and 299 females) and 75 (cohort NORA75, 143 males and 180 females). Methods: Body composition was measured with BIA (BIA-101, RJL system, Detroit) in both cohorts and was estimated by a four-compartment (4C) model from total body water (TBW) and total body potassium (TBK) in a sub-sample of the NORA75 cohort. The FFM[SUBBIA] was validated against the FFM from the 4C model (FFM[SUB4C]). Results: The FFM[SUBBIA] correlated well with FFM[SUB4C] (r=0.95, SEE =2.64 kg). The FFM[SUBBIA] (kg) in 70-y-old males and females were 58.5±75.4 and 43.4±4.4, and for 75-y-old males and females were 56.1±4.7 and 42.5±4, respectively. The body fat in kg (FM) among 70-y-old males and females were 25.2±8.1 and 25.7±8.4, and for 75-y-old males and females were 21.7±7.1 and 22.8+7.2, respectively. The percent body fat (BF%) among 70-y-old males and females were 29.5±5.8 and 36.3±6.4, and for 75-y-old males and females were 27.3±6 and 34.1±76.1, respectively. Conclusion: The FFM, FM and BF% from this study might be used as reference values for Swedish elderly aged 70 and 75 y. Sponsorship: See acknowledgement. [ABSTRACT FROM AUTHOR]
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- 2003
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28. Body mass index, weight change and mortality in the elderly. A 15 y longitudinal population study of 70 y olds.
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Dey, D K, Rothenberg, E, Sundh, V, Bosaeus, I, and Steen, B
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- 2001
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29. Height and body weight in the elderly. I. A 25-year longitudinal study of a population aged 70 to 95 years.
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Dey, D K, Rothenberg, E, Sundh, V, Bosaeus, I, and Steen, B
- Abstract
Objective: To describe longitudinal changes in height and body weight between the ages of 70 and 95 y.Design: Longitudinal cohort study with representative sample of 70-y-olds.Setting: Department of Geriatric Medicine, Göteborg University, Sweden.Subjects: 449 males and 524 females, aged 70 y, living in Göteborg were examined in 1971-72 and this study population participated on 11 occasions during a 25-year follow-up.Results: Mean height decreased 4 and 4.9 cm in males and females respectively and the trend was significant between the ages of 70 and 95 y in both sexes. Between 70 and 75 y of age, a significant difference was found between quintiles of body height where in the highest quintile height was lowered by 0.4 and 0. 3 cm/y, in males and females respectively, and in the lowest quintile by 0.1 cm/y in both sexes. Mean body weight decreased 3.2 and 5.1 kg in males and females respectively, from age 70 to 95 y. The trend was significant over 22 and 20 y for males and females, respectively. Between the ages of 70 and 80 y, individuals in highest quintile of body weight decreased at a rate of 0.8 and 0.6 kg/y, three times higher than those in lowest quintile. Due to the decrease in both height and weight over time, body mass index (BMI) was less affected.Conclusion: Height, body weight and BMI decreased significantly in both sexes after age 70 y, and there was a gender difference in the trend. The results can be used as reference data for Swedish elderly and might be of importance to the understanding of anthropometry with the ageing process.Sponsorship: See acknowledgements. [ABSTRACT FROM AUTHOR]- Published
- 1999
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30. Symphytum officinale augments osteogenesis in human bone marrow-derived mesenchymal stem cells in vitro as they differentiate into osteoblasts.
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Dey, D, Jingar, P, Agrawal, S, Shrivastava, V, Bhattacharya, A, Manhas, J, Garg, B, Ansari, M.T., Mridha, A.R., Sreenivas, V, Khurana, A, and Sen, S
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OSTEOBLAST metabolism , *ALKALINE phosphatase , *BONE marrow , *BONE growth , *ENZYME-linked immunosorbent assay , *FLOW cytometry , *GENE expression , *HOMEOPATHY , *POLYMERASE chain reaction , *RESEARCH funding , *STEM cells , *PLANT extracts , *IN vitro studies ,THERAPEUTIC use of plant extracts - Abstract
Mesenchymal stem cells (MSCs) are multipotent stem cells possessing regenerative potential. Symphytum officinale (SO) is a medicinal plant and in homoeopathic literature, believed to accelerate bone healing. This study aimed to determine if homoeopathic doses of SO could augment osteogenesis in MSCs as they differentiate into osteoblasts in vitro. Bone marrow samples were obtained from patients who underwent bone grafting procedures (n = 15). MSCs were isolated, expanded and characterized by flow cytometry (CD90, CD105). Cytotoxicity of SO was evaluated by MTT assay. Osteogenic differentiation was induced in MSCs with β-glycerophosphate, ascorbic acid and dexamethasone over 2 weeks. Different homoeopathic doses of SO (MT, 3C, 6C, 12C and 30C) were added to the basic differentiation medium (BDM) and efficiency of MSCs differentiating into osteoblasts were measured by evaluating expression of Osteocalcin using flow cytometry, and alkaline phosphatase activity using ELISA. Gene expression analyses for osteoblast markers (Runx-2, Osteopontin and Osteocalcin) were evaluated in differentiated osteoblasts using qPCR. Flow cytometry (CD90, CD105) detected MSCs isolated from bone marrow (93–98%). MTT assay showed that the selected doses of SO did not induce any cytotoxicity in MSCs (24 hours). The efficiency of osteogenic differentiation (2 weeks) for different doses of Symphytum officinale was determined by flow cytometry (n = 10) for osteoblast marker, Osteocalcin, and most doses of Symphytum officinale enhanced osteogenesis. Interestingly, gene expression analysis for Runx-2 (n = 10), Osteopontin (n = 10), Osteocalcin (n = 10) and alkaline phosphatase activity (n = 8) also showed increased osteogenesis with the addition of Symphytum officinale to BDM, specially mother tincture. Our findings suggest that homoeopathic dose (specially mother tincture) of Symphytum officinale has the potential to enhance osteogenesis. Image 1 [ABSTRACT FROM AUTHOR]
- Published
- 2020
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31. Selective breaking of bonds in water with intense, 2-cycle, infrared laser pulses.
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Mathur, D., Dota, K., Dey, D., Tiwari, A. K., Dharmadhikari, J. A., Dharmadhikari, A. K., De, S., and Vasa, P.
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INFRARED lasers , *WATER , *CHEMICAL bonds , *POTENTIAL energy surfaces , *DISSOCIATION (Chemistry) , *MOLECULAR dynamics - Abstract
One of the holy grails of contemporary science has been to establish the possibility of preferentially breaking one of several bonds in a molecule. For instance, the two O-H bonds in water are equivalent: given sufficient energy, either one of them is equally likely to break. We report bond-selective molecular fragmentation upon application of intense, 2-cycle pulses of 800 nm laser light: we demonstrate up to three-fold enhancement for preferential bond breaking in isotopically substituted water (HOD). Our experimental observations are rationalized by means of ab initio computations of the potential energy surfaces of HOD, HOD+, and HOD2+ and explorations of the dissociation limits resulting from either O-H or O-D bond rupture. The observations we report present a formidable theoretical challenge that need to be taken up in order to gain insights into molecular dynamics, strong field physics, chemical physics, non-adiabatic processes, mass spectrometry, and time-dependent quantum chemistry. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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32. Automated coronary artery tracking in contrastenhanced whole-heart coronary magnetic resonance angiography at 3.0T.
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Dey, D., Schuhbaeck, Q. Yang, Z. Fan, Germano, G., Achenbach, S., D. Li, and Slomka, P.
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CORONARY artery physiology , *AUTOMATION , *CARDIOVASCULAR disease diagnosis , *CONFERENCES & conventions , *MAGNETIC resonance angiography - Abstract
An abstract of the article "Automated coronary artery tracking in contrastenhanced whole-heart coronary magnetic resonance angiography at 3.0T," by D. Dey and colleagues is presented.
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- 2013
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33. Investigation on ionic states of 1,2-Dipalmitoyl-sn-glycero-3-phosphorylcholine (DPPC) using organic laser dyes: A FRET study.
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Roy, Arpan Datta, Saha, Jaba, Dey, D., Bhattacharjee, D., and Hussain, Syed Arshad
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FLUORESCEIN , *RHODAMINES , *LASER dyes , *FLUORESCENCE resonance energy transfer , *AMBIENT conditions (Electronics) - Abstract
Fluorescence Resonance Energy Transfer (FRET) between two organic dyes Fluorescein and Rhodamine 6G were successfully investigated in aqueous solution in presence and absence of 1,2-Dipalmitoyl-sn-glycero-3-phosphorylcholine (DPPC) at different pH. Spectroscopic studies suggest that both the dyes were present mainly as monomer in solution. FRET occurred from Fluorescein to Rhodamine 6G in solutions. Energy transfer efficiency increases in presence of DPPC and the maximum efficiency was 59.3% when the concentration of DPPC was 1.4×10 −4 M at ambient condition. pH plays a crucial role in this investigation as the energy transfer efficiency was found to change in presence of DPPC at different pH. It has been demonstrated that with proper calibration it is possible to use the present system under investigation to realize various ionic states of DPPC by observing the change in FRET efficiency between these two dyes. [ABSTRACT FROM AUTHOR]
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- 2017
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34. Clonal Elimination of the Pathogenic Allele as Diagnostic Pitfall in SAMD9L -Associated Neuropathy.
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Eggermann, K., Meyer, R., Begemann, M., Dey, D., Bültmann, E., Kurth, I., Korenke, G. C., and Knopp, C.
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SINGLE nucleotide polymorphisms , *GENETIC variation , *HETEROZYGOSITY , *DNA copy number variations , *NEUROPATHY , *ALLELES - Abstract
Background: Heterozygous gain-of-function variants in SAMD9L are associated with ataxia-pancytopenia syndrome (ATXPC) and monosomy 7 myelodysplasia and leukemia syndrome-1 (M7MLS1). Association with peripheral neuropathy has rarely been described. Methods: Whole-exome sequencing (WES) from DNA extracted from peripheral blood was performed in a 10-year-old female presenting with demyelinating neuropathy, her similarly affected mother and the unaffected maternal grandparents. In addition to evaluation of single nucleotide variants, thorough work-up of copy number and exome-wide variant allele frequency data was performed. Results: Combined analysis of the mother's and daughter's duo-exome data and analysis of the mother's and her parents' trio-exome data initially failed to detect a disease-associated variant. More detailed analysis revealed a copy number neutral loss of heterozygosity of 7q in the mother and led to reanalysis of the exome data for respective sequence variants. Here, a previously reported likely pathogenic variant in the SAMD9L gene on chromosome 7q (NM_152703.5:c.2956C>T; p.(Arg986Cys)) was identified that was not detected with standard filter settings because of a low percentage in blood cells (13%). The variant also showed up in the daughter at 32%, a proportion well below the expected 50%, which in each case can be explained by clonal selection processes in the blood due to this SAMD9L variant. Conclusion: The report highlights the specific pitfalls of molecular genetic analysis of SAMD9L and, furthermore, shows that gain-of-function variants in this gene can lead to a clinical picture associated with the leading symptom of peripheral neuropathy. Due to clonal hematopoietic selection, displacement of the mutant allele occurred, making diagnosis difficult. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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35. Time growing frequency sweep signal based insulation condition monitoring in frequency domain spectroscopy.
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Pradhan, A. K., Chatterjee, B., Dey, D., and Chakravorti, S.
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SIGNAL processing , *ELECTRIC insulators & insulation , *ALTERNATING currents , *ELECTRIC potential , *DIELECTRIC materials , *POLARIZATION (Electricity) - Abstract
When an alternating voltage is applied to a dielectric material, dipoles in the material try to align in the direction of the applied voltages and polarization process starts. For multi-dielectric media especially in which a liquid interface is involved, such as oilpaper insulation, interfacial polarization is predominantly active among all polarization processes. This interfacial polarization is a very slow process and is effective in lower frequency range. This interfacial polarization reflects the inherent condition of the oilpaper insulation. Due to this reason, frequency domain spectroscopy is performed in lower frequency range to assess the condition of oil-paper insulation. So, the time required for frequency response measurement using conventional frequency domain spectroscopy is quite long. Considering the aforesaid facts, a different procedure has been taken here to measure the dielectric response in a significantly lesser time keeping the entire frequency range of conventional frequency domain spectroscopy. Instead of using pure sinusoidal excitation voltages over wide frequency range, dielectric response current has been measured using excitation having time growing frequency sweep (TGFS) signal. For this purpose, test samples that emulate the oil-paper insulation of real-life transformer have been prepared in the laboratory. The moisture contents of the test samples have been kept different to investigate the reliability of the proposed method. A setup has been made in the laboratory to measure dielectric response currents using the both excitations. In order to investigate the applicability of the proposed method, experiment has also been performed on actual transformers. It has been observed that the use of excitation signal having time growing frequency sweep provides almost similar information regarding insulation condition as obtained by the use of conventional sinusoidal excitation voltages. Hence, the proposed method is capable of reduction in time in FDS nearly by an amount of 85%. [ABSTRACT FROM PUBLISHER]
- Published
- 2016
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36. Coronary Artery Calcium Density and Risk of Cardiovascular Events: A Systematic Review and Meta-Analysis.
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Yong, Y., Giovannucci, J., Pang, S., Hong, W., Han, D., Berman, D., Dey, D., Nicholls, S., Nerlekar, N., and Lin, A.
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CORONARY artery calcification , *CARDIOVASCULAR diseases risk factors , *DENSITY - Published
- 2024
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37. EE11 Budget Impact Analysis of a Triple-Agent Fixed-Dose Combination of 1.2% Clindamycin Phosphate, 0.15% Adapalene, and 3.1% Benzoyl Peroxide Topical Gel for the Treatment of Patients With Moderate-to-Severe Acne Vulgaris in the US.
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Thomas, A, Harper, J, Soni, P, Dey, D, Bhattacharyya, S, Cohen, B, Lin, T, Olujohungbe, O, Samson, A, Bumpass, B, Jospeh, G, and Dashputre, A
- Published
- 2024
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38. Tapetum-specific expression of harpin causes male sterility in transgenic tobacco.
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Madhuri, B., Raut, S., Dey, D., Nazneen, A., Uma, B., and Podile, A.
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TAPETUM , *EXINE , *HARPINS , *PLANT cells & tissues , *PLANT diseases - Abstract
Harpin, an elicitor molecule of bacterial origin induces hypersensitive response (HR) in non-host plants. In an attempt to induce male sterility, harpin was tagged with a signal peptide and expressed downstream to tapetum-specific TA29 promoter resulting in extracellular secretion, subsequent degeneration of tapetum and development of male sterility in tobacco. Putative transgenics were analyzed by PCR amplification of transgene, semiquantitative RT-PCR analysis from total RNA extracts from anther tissue with transgene specific probe, Western blotting using polyclonal antibody raised against harpin, by transmission and scanning electron microscopy, and by confocal microscopy of anthers and pollen at various stages of development. Varying degrees of male sterility (30-100 %) was observed with plants showing complete and partial male sterility as well as several morphological variations were seen especially in leaves and flowers. Further, some of the transgenics showed un-induced of HR-like local lesions in the vegetative tissues. Harpin got deposited on the pollen grains upon tapetal degeneration resulting in significant alterations in the morphology of pollen cell wall. However, megagametogenesis was not affected in complete and partial male sterile plants and female gametes were completely fertile. The complete male sterility was attributed to premature tapetal cell death due to sufficient extracellular harpin accumulation whereas insufficient protein content might be the reason for partial male sterility. These findings indicate the possible use of cytotoxic harpin for the development of male sterile plants. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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39. Chloroform decreases rumen methanogenesis and methanogen populations without altering rumen function in cattle
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Knight, T., Ronimus, R.S., Dey, D., Tootill, C., Naylor, G., Evans, P., Molano, G., Smith, A., Tavendale, M., Pinares-Patiño, C.S., and Clark, H.
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PHYSIOLOGICAL effects of chloroform , *RUMEN microbiology , *METHANOGENS , *CATTLE physiology , *GREENHOUSE gases , *POLYKETIDES , *COENZYMES , *DENATURING gradient gel electrophoresis - Abstract
Abstract: Anthropogenic CH4 emissions are widely recognised as a world wide problem due to their global warming potential and because they represent a loss of dietary energy to ruminants. Few recent studies have examined medium or long term effects of methanogen inhibitors on rumen functional parameters and development of resistance to them. The aim of our study was to investigate medium term effects of a potent methanogen inhibitor on methanogen populations using molecular techniques and rumen function. Six rumen fistulated cows were divided into two groups and allocated to control and chloroform treatment and fed at a fixed rate of 8.4kgdry matter (DM)/cow/d. After 7d of acclimatization, treatment cows were dosed daily with 1.5ml of chloroform in 30ml of sunflower oil for 42 d, while control cows only received sunflower oil. Key indicators of rumen function monitored included rumen pH, rumen fill, apparent feed digestibility, apparent rumen digesta retention time, total protozoa numbers, and volatile fatty acid (VFA) and NH3 concentrations. Methane emissions were monitored using the SF6 tracer technique, and methanogens using denaturing gradient gel electrophoresis (DGGE) and four clone libraries. Methanogens and acetogens were monitored in a single cow by most probable number culturing methods. Chloroform, a known inhibitor of methanogenesis, resulted in an immediate and dramatic decrease in CH4 emissions and methanogen numbers, with the effect being most pronounced 1wk after the start of the treatment. Thereafter, CH4 emissions increased slowly, reaching 62% of pre-treatment levels by d 42. The effect on CH4 emissions was reflected by a near complete disappearance of DGGE bands associated with methanogens in treated cows. This response was particularly obvious for Methanobrevibacter species. There were no effects of chloroform on apparent rumen digesta retention time, apparent feed digestibility, pH, NH3 or rumen fill. Total protozoa numbers tended to increase during the study in both groups. Total VFA concentrations did not change with chloroform treatment, but the acetate:propionate ratio during the period of dosing was lower (P<0.01) for treated cows (1.9) in the middle of the study (d 23) than in the control cows (2.7), but did not differ after treatment ceased at d 53. Despite profound effects of chloroform on CH4 emissions and methanogens, chloroform did not appear to alter basic rumen function. Whether a reduction in CH4 loss improves feed conversion efficiency requires further research using substances which have a sustained anti-methanogenic effect. This article is part of the special issue entitled: Greenhouse Gases in Animal Agriculture – Finding a Balance between Food and Emissions, Guest Edited by T.A. McAllister, Section Guest Editors; K.A. Beauchemin, X. Hao, S. McGinn and Editor for Animal Feed Science and Technology, P.H. Robinson. [Copyright &y& Elsevier]
- Published
- 2011
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40. Immobilization of single strand DNA on solid substrate
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Hussain, S.A., Paul, P.K., Dey, D., Bhattacharjee, D., and Sinha, S.
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NUCLEIC acids , *DNA , *GENES , *SPECTRUM analysis - Abstract
Abstract: This Letter reports the immobilization of DNA onto a solid support by electrostatic interaction with a polycation poly(allylamine hydrochloride) (PAH). The films were analyzed by UV–vis spectroscopy. The significant observation is that single stranded DNA gets immobilized on the PAH backbone of Layer-by-Layer (LbL) films when the films are fabricated above the melting temperature of DNA. Singly stranded DNA immobilized in the LbL films is not restored into double stranded DNA at room temperature. [Copyright &y& Elsevier]
- Published
- 2007
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41. Prevalence of metabolic syndrome in an elderly Swedish population.
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Gause-Nilsson, I., Gherman, S., Kumar Dey, D., Kennerfalk, A., and Steen, B.
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METABOLIC syndrome , *OBESITY , *BLOOD sugar , *HYPERTENSION in old age , *MEDICAL care surveys , *OLDER people , *HIGH density lipoproteins - Abstract
The prevalence of the metabolic syndrome in different elderly European populations has not been well studied. The aim of this study was to measure the prevalence of metabolic syndrome, as well as its individual components, in an elderly Swedish cohort. A random sample of 778 individuals (372 men and 406 women) was selected from a 70-year-old cohort in the H70 study, a gerontological and geriatric population study carried out in Gothenburg, Sweden. The study included medical and treatment history assessments, laboratory procedures and physical examinations to determine the presence of each of the five components of the metabolic syndrome as defined by the National Cholesterol Education Program Adult Treatment Panel III. Of the 508 adults (243 men and 265 women) included in the study, 22.6% had metabolic syndrome. The prevalence was higher in men (26.3%) than in women (19.2%). One third of the total sample had at least one of the five risk factors for metabolic syndrome. High blood pressure (≥130/85 mmHg or use of antihypertensive/diuretic medication) was the most prevalent risk factor in both men (68.3%) and women (50.2%), while abdominal obesity was the overall second most common risk factor (27.2% of men and 42.7% of women). The prevalence of high fasting plasma glucose (≥110 mg/dl or use of antidiabetic medication) was 29.0% in men and 19.1% in women. Metabolic syndrome was prevalent in a significant proportion of this elderly Swedish population, highlighting the underdiagnosis of a condition that is important to treat. [ABSTRACT FROM AUTHOR]
- Published
- 2006
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42. Low‐complexity leakage current acquisition system for transmission line insulators employing GSM voice channel.
- Author
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Ghosh, R., Chatterjee, B., Dey, D., and Chakravorti, S.
- Abstract
With the rapid advancements in electronics and in communication infrastructures, the deployment of low‐complexity devices for power system monitoring has become an active area of research. For the large‐scale deployment of monitoring devices, robust and economical remote data acquisition systems for power system monitoring are required. Keeping this in mind, the scheme of a remote leakage current acquisition system for high‐voltage insulators that may be employed for remote monitoring purposes is described. A low‐complexity method is adopted for the extraction of harmonic information from the leakage current signal. Unlike existing remote insulator‐monitoring techniques that employ a dedicated fibre‐optic network and satellite communication, the mobile communication voice channel is used to communicate the data to a central location for analysis. This provides an economical solution for the remote monitoring of insulators that may be used for large‐scale deployment. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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43. Synthesis, engineering, and theory of 2D van der Waals magnets.
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Blei, M., Lado, J. L., Song, Q., Dey, D., Erten, O., Pardo, V., Comin, R., Tongay, S., and Botana, A. S.
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CONDENSED matter physics , *SPIN transfer torque , *MAGNETIC fields , *MAGNETIC materials , *MATERIALS science , *VAN der Waals forces , *MAGNETS - Abstract
The recent discovery of magnetism in monolayers of two-dimensional van der Waals materials has opened new venues in materials science and condensed matter physics. Until recently, two-dimensional magnetism remained elusive: Spontaneous magnetic order is a routine instance in three-dimensional materials but it is not a priori guaranteed in the two-dimensional world. Since the 2016 discovery of antiferromagnetism in monolayer FePS3 by two groups and the subsequent demonstration of ferromagnetic order in monolayer CrI3 and bilayer Cr2Ge2Te6, the field changed dramatically. Within several years of scientific discoveries focused on 2D magnets, novel opportunities have opened up in the field of spintronics, namely spin pumping devices, spin transfer torque, and tunneling. In this review, we describe the state of the art of the nascent field of magnetic two-dimensional materials focusing on synthesis, engineering, and theory aspects. We also discuss challenges and some of the many different promising directions for future work, highlighting unique applications that may extend even to other realms, including sensing and data storage. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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44. Willingness to pay for kidney transplantation among chronic kidney disease patients in Ghana.
- Author
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Boima, V., Agyabeng, K., Ganu, V., Dey, D., Yorke, E., Amissah-Arthur, M. B., Wilson, A. A., Yawson, A. E., Mate-Kole, C. C., and Nonvignon, J.
- Subjects
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WILLINGNESS to pay , *KIDNEY transplantation , *CHRONIC kidney failure , *CHRONICALLY ill , *CONTINGENT valuation - Abstract
Background: Kidney transplantation is the preferred treatment for patients with end stage renal disease. However, it is largely unavailable in many sub-Sahara African countries including Ghana. In Ghana, treatment for end stage renal disease including transplantation, is usually financed out-of-pocket. As efforts continue to be made to expand the kidney transplantation programme in Ghana, it remains unclear whether patients with Chronic Kidney Disease (CKD) would be willing to pay for a kidney transplant. Aim: The aim of the study was to assess CKD patients' willingness to pay for kidney transplantation as a treatment option for end stage renal disease in Ghana. Methods: A facility based cross-sectional study conducted at the Renal Outpatient clinic and Dialysis Unit of Korle-Bu Teaching Hospital among 342 CKD patients 18 years and above including those receiving haemodialysis. A consecutive sampling approach was used to recruit patients. Structured questionnaires were administered to obtain information on demographic, socio-economic, knowledge about transplant, perception of transplantation and willingness to pay for transplant. In addition, the INSPIRIT questionnaire was used to assess patients' level of religiosity and spirituality. Contingent valuation method (CVM) method was used to assess willingness to pay (WTP) for kidney transplantation. Logistic regression model was used to determine the significant predictors of WTP. Results: The average age of respondents was 50.2 ± 17.1 years with most (56.7% (194/342) being male. Overall, 90 out of the 342 study participants (26.3%, 95%CI: 21.7–31.3%) were willing to pay for a kidney transplant at the current going price (≥ $ 17,550) or more. The median amount participants were willing to pay below the current price was $986 (IQR: $197 –$1972). Among those willing to accept (67.3%, 230/342), 29.1% (67/230) were willing to pay for kidney transplant at the prevailing price. Wealth quintile, social support in terms of number of family friends one could talk to about personal issues and number of family members one can call on for help were the only factors identified to be significantly predictive of willingness to pay (p-value < 0.05). Conclusion: The overall willingness to pay for kidney transplant is low among chronic kidney disease patients attending Korle-Bu Teaching Hospital. Patients with higher socio-economic status and those with more family members one can call on for help were more likely to pay for kidney transplantation. The study's findings give policy makers an understanding of CKD patients circumstances regarding affordability of the medical management of CKD including kidney transplantation. This can help develop pricing models to attain an ideal poise between a cost effective but sustainable kidney transplant programme and improve patient access to this ultimate treatment option. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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45. Knowledge and Willingness to Donate Kidneys for Transplantation in Ghana: A Cross-Sectional Survey.
- Author
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Boima, V., Ganu, V., Yorke, E., Dey, D., Amissah-Arthur, M.B., Agyabeng, K., Yawson, A., Lartey, M., and Mate-Kole, C.C.
- Subjects
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KIDNEY transplantation , *CHRONIC kidney failure , *AGE groups , *HEMODIALYSIS , *BASIC education - Abstract
The main treatment modalities for chronic kidney disease (CKD) are dialysis and kidney transplantation. While kidney transplantation provides better survival and quality of life outcomes, it is a new treatment option in Ghana. Finding kidney donors for transplant may be a major challenge due to varied views of the public. This cross-sectional study was carried out in 5 purposively selected communities in the Greater Accra region in Ghana. Structured questionnaires and standardized instruments were used to assess sociodemographic characteristics, spirituality, and perception of kidney transplantation. The mean age of the 480 participants was 29.60 ± 10.65 years. The proportion of men was 51%. The average score for knowledge of participants on kidney donation was 4.8 ± 2.6. The level of spirituality score was 25.4 ± 3.89. Approximately 48% (231/480) of participants were willing to donate a kidney while still alive. Willingness to donate when dead was 72% (344/480). Willingness to donate a kidney when dead was significantly lower among the participants in the older age groups. High level of knowledge about kidney transplantation, being employed, basic formal education, and never married were associated with willingness to donate kidney (P <.05). Our results suggest that participants have a low level of knowledge regarding kidney transplantation, while about two-thirds are willing to donate only after death. Continuous public education is key to raise public awareness of the need for kidney transplants. This will support the Ministry of Health in their efforts to institute a kidney transplant program in Ghana. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
46. CO110 Systematic Literature Review and Network Meta-Analysis to Assess the Comparative Efficacy of Topical Fixed-Dose Combinations for Moderate to Severe Acne Vulgaris as Measured By Lesion Counts.
- Author
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Harper, J., Baldwin, H., Ghosh, B., Paul Choudhury, S., Rai, D., Aman, M.S., Choudhury, A.R., Dey, D., Dutta, S., Bhattacharyya, S., Lin, T., Dashputre, A.A., Jospeh, G., and Tan, J.
- Subjects
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ACNE - Published
- 2023
- Full Text
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47. Sex differences in coronary plaque composition evaluated by coronary computed tomography angiography in newly diagnosed Type 2 diabetes: association with low‐grade inflammation.
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Mrgan, M., Gram, J., Hecht Olsen, M., Dey, D., Linde Nørgaard, B., and Rønnow Sand, N. P.
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TYPE 2 diabetes diagnosis , *AGE distribution , *BIOMARKERS , *BLOOD vessels , *C-reactive protein , *CARDIOVASCULAR diseases risk factors , *COMPUTED tomography , *COMPUTER software , *CORONARY disease , *FIBRIN , *FIBRINOGEN , *INFLAMMATION , *SEX distribution - Abstract
Aim: To determine differences in coronary plaque composition and inflammatory biomarkers between men and women with newly diagnosed Type 2 diabetes without known cardiovascular disease. Methods: A total of 88 people with newly diagnosed (<1 year) Type 2 diabetes underwent contrast‐enhanced coronary computed tomography angiography. Advanced coronary plaque analysis was performed using semi‐automated software. Plasma concentrations of inflammatory biomarkers were determined. Results: There were no significant differences between men (n=60) and women (n=28) regarding age or cardiovascular risk factors (all P>0.05). The median (quartiles) serum levels of fibrinogen [10.9 (9.8–12.6) μmol/l vs 9.7 (8.8–10.9) μmol/l], fibrin d‐dimer [0.3 (0.2–0.4) mg/l vs 0.27 (0.2–0.4) mg/l] and C‐reactive protein [3.1 (1.1–5.2) mg/l vs (0.8–2.6) 1.6 mg/l] were significantly higher in women (all P<0.05). Overall, men more often had multi‐vessel involvement [28 men (47%) vs 4 women (14%)], and higher total plaque burden [median (quartiles) 11.6 (2.3–36.0)% vs 2.0 (0.4–5.4)%; both P<0.05]. The median (quartiles) total plaque volume [269.9 (62.6–641.9) mm3 vs 61.1 (7.6–239.9) mm3] and absolute calcified plaque volume [33.5 (8.3–148.3) mm3 vs 4.7 (0.9–17.3) mm3] were higher in men (both P<0.05). Women had a lower relative proportion of the calcified plaque component [median (quartiles) 7.8 (4.7–15.4)% vs 23.7 (8.4–31.1)%] and a higher relative proportion (median [quartiles]) of the non‐low‐density non‐calfied plaque component [77.6 (66.0–86.0)% vs 63.6 (54.0–72.9)%; both P<0.05]. Conclusions: In people with newly diagnosed Type 2 diabetes, women had lower absolute coronary plaque volumes but a more unfavourable plaque composition and enhanced systemic inflammation compared with men. What's new?: It is known that Type 2 diabetes increases the risk of developing coronary artery disease more markedly in women than in men, but differences in coronary plaque composition between the sexes are poorly elucidated.This study found that women have smaller absolute volumes of coronary plaque components but a more unfavourable coronary plaque structure and enhanced systemic inflammation.The reported difference in plaque composition between men and women with a new diagnosis of Type 2 diabetes might be the basis for larger studies evaluating the impact of sex‐differentiated therapeutic strategies at an early stage of Type 2 diabetes to prevent the development and progression of cardiovascular disease. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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- View/download PDF
48. Coronary Atherosclerotic Plaque Burden and Composition as Assessed on Computed Tomography Angiography in East Asian and Caucasian Populations.
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Ihdayhid, A., Goeller, M., Dey, D., Adams, D., Nerlekar, N., Yap, G., Thakur, U., Cameron, J., Seneviratne, S., Achenbach, S., and Ko, B.
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- 2018
- Full Text
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49. Low-complexity leakage current acquisition system for transmission line insulators employing GSM voice channel.
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Ghosh, R., Chatterjee, B., Dey, D., and Chakravorti, S.
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MATHEMATICAL models , *STRAY currents , *STRIP transmission lines , *TELECOMMUNICATION satellites , *FIBER optical sensors , *MOBILE communication systems - Abstract
With the rapid advancements in electronics and in communication infrastructures, the deployment of low-complexity devices for power system monitoring has become an active area of research. For the large-scale deployment of monitoring devices, robust and economical remote data acquisition systems for power system monitoring are required. Keeping this in mind, the scheme of a remote leakage current acquisition system for high-voltage insulators that may be employed for remote monitoring purposes is described. A low-complexity method is adopted for the extraction of harmonic information from the leakage current signal. Unlike existing remote insulator-monitoring techniques that employ a dedicated fibre-optic network and satellite communication, the mobile communication voice channel is used to communicate the data to a central location for analysis. This provides an economical solution for the remote monitoring of insulators that may be used for large-scale deployment. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
50. Development of Multiwell-Plate Methods Using Pure Cultures of Methanogens To Identify New Inhibitors for Suppressing Ruminant Methane Emissions.
- Author
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Weimar, M. R., Cheung, J., Cook, G. M., Dey, D., Carbone, V., Schofield, L. R., Ronimus, R. S., McSweeney, C., Morrison, M., Kobayashi, Y., and Whitman, W. B.
- Subjects
- *
METHANOGENS , *RUMEN microbiology , *ANAEROBIC metabolism , *METHANOCOCCUS maripaludis , *METHANE & the environment - Abstract
Hydrogenotrophic methanogens typically require strictly anaerobic culturing conditions in glass tubes with overpressures of H2 and CO2 that are both time-consuming and costly. To increase the throughput for screening chemical compound libraries, 96-well microtiter plate methods for the growth of a marine (environmental) methanogen Methanococcus maripaludis strain S2 and the rumen methanogen Methanobrevibacter species AbM4 were developed. A number of key parameters (inoculum size, reducing agents for medium preparation, assay duration, inhibitor solvents, and culture volume) were optimized to achieve robust and reproducible growth in a high-throughput microtiter plate format. The method was validated using published methanogen inhibitors and statistically assessed for sensitivity and reproducibility. The Sigma-Aldrich LOPAC library containing 1,280 pharmacologically active compounds and an in-house natural product library (120 compounds) were screened against M. maripaludis as a proof of utility. This screen identified a number of bioactive compounds, and MIC values were confirmed for some of them against M. maripaludis and M. AbM4. The developed method provides a significant increase in throughput for screening compound libraries and can now be used to screen larger compound libraries to discover novel methanogen-specific inhibitors for the mitigation of ruminant methane emissions. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
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