209 results on '"SPECTRUM analysis"'
Search Results
2. New withanolides from leaves along with alkyl glucoside from roots and stem as well as variations in withanolide contents in leaves of accessions of Withania somnifera, Ashwagandha- the Indian ginseng$.
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Lal, Payare, Misra, Laxminarain, Sangwan, Neelam S., and Sangwan, Rajender S.
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ORGANIC compound analysis ,IN vitro studies ,RESEARCH funding ,PLANT stems ,PLANT roots ,PHYTOCHEMICALS ,DESCRIPTIVE statistics ,PLANT extracts ,PHYTOSTEROLS ,GLYCOSIDES ,MOLECULAR structure ,SPECTRUM analysis ,GINSENG ,LEAVES ,CHROMATOGRAPHIC analysis - Abstract
Based on the major components in the leaves, the ashwagandha has been found to exist in several chemotypic forms in India. From the leaves of various accessions of Withania somnifera, which were maintained in our institute, three new steroids namely, 4-acetoxy-20β-hydroxy-1-oxo-witha-2,5,24-trienolide (7), 24,25-dihydro-14α-hydroxy withanolide D (9), 5α,6β,17α,27-tetrahydroxy-1-oxo-witha-2,24-dienolide (12) together with thirteen known withanolides were identified by spectroscopic methods. From the roots and stem of one accession and leaves of another, a new alkyl ester glucoside (4) has also been isolated. The new withanolides 7, 9 and 12 have been tentatively named as withanolide 135 A, withanolide 135B and withanolide 108, respectively. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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3. Evaluation of therapeutic role of harmaline: in vitro cytotoxicity targeting nucleic acids.
- Author
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Bhattacharjee, Paromita, Sarkar, Paromita, and Bhadra, Kakali
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ALKALOIDS , *ANTINEOPLASTIC agents , *APOPTOSIS , *CELLULAR signal transduction , *BIOLOGICAL products , *IMMUNODIAGNOSIS , *PHYTOCHEMICALS , *CYTOTOXINS , *CELL lines , *NUCLEIC acids , *MOLECULAR structure , *SPECTRUM analysis , *GENETICS , *CELL surface antigens ,THERAPEUTIC use of alkaloids - Abstract
Use of small molecules as valuable drugs against diseases is still an indefinable purpose due to the lack of in-detail knowledge regarding proper bio-target identification, specificity aspects, mode-mechanism of binding and proper in vitro study. Harmaline, an important beta-carboline alkaloid, shows effective anti-proliferative action against different types of human cancers and is also found to be a nucleic acid targeting natural molecule. This review sought to address the different signal pathways of apoptosis by harmaline in different cancer cell lines and simultaneously to characterize the structure activity aspects of the alkaloid with different motifs of nucleic acid to show its preference, biological efficacy and genotoxicity. The results open up new insights for the design and development of small molecule-based nucleic acid therapeutic agents. [ABSTRACT FROM AUTHOR]
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- 2024
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4. Discerning animal-sourced food in diet using isotope analysis of human scalp hair and fingernails.
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Agrawal, Gunjan and Sanyal, Prasanta
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NITROGEN analysis , *CARBON analysis , *ISOTOPIC analysis , *FOOD habits , *BIOMARKERS , *INFERENTIAL statistics , *STATISTICS , *KRUSKAL-Wallis Test , *NAILS (Anatomy) , *MEAT , *VEGETARIANISM , *VEGETABLES , *ANALYSIS of variance , *POULTRY , *CONFIDENCE intervals , *FOOD consumption , *SCALP , *NUTRITIONAL value , *MANN Whitney U Test , *METABOLISM , *PLANT-based diet , *FOOD animals , *T-test (Statistics) , *DIETARY sucrose , *HAIR , *DESCRIPTIVE statistics , *GRAIN , *ANALYTICAL chemistry techniques , *DATA analysis software , *DATA analysis , *DIETARY proteins , *SPECTRUM analysis - Abstract
Purpose: Diet-related diseases are advancing as the leading cause of death globally. As self-reporting of diet by patients can be associated with errors, stable isotopes of human tissues can be used to diagnose diseases, understand physiology, and detect change in diet. This study investigates the effect of type and amount of food on the nitrogen and carbon concentration (Nconc and Cconc) and isotopic composition (δ15N and δ13C) in human scalp hair and fingernails. Methods: A total of 100 residents participated in the study whereas only 74 individuals provided complete diet history. Sixty-six food items majorly available to them were also collected. The Nconc, Cconc, δ15N and δ13C values of human hair, nails and food items were determined. Results: The Nconc, Cconc, δ15N and δ13C values between plant-sourced and animal-sourced food items, as well as human hair and nail tissue were significantly different (p < 0.05). The δ15N value of human tissues was distinct between lacto-vegetarians and omnivores by 0.9‰. The δ15N and δ13C values of human tissues increased by 0.4–0.5‰ with every 5% increase in the consumption of animal protein. Conclusions: The study helps to demarcate lacto-vegetarians from omnivores, and estimate the percentage of animal protein in diet based on the dual isotope values of human tissues. It also acts as a reference to determine isotopic composition of hair tissue provided the isotope value of nail tissue is known and vice versa. [ABSTRACT FROM AUTHOR]
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- 2024
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5. Performance Analysis of a Dynamic Spectrum Assignment Technique for 6G.
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Iyer, Sridhar
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SPECTRUM analysis , *ENERGY consumption , *CONSUMERS , *DIGITAL subtraction angiography - Abstract
In the current work, we formulate a dynamic spectrum assignment (DSA) technique to allocate the experimental licensed 95 GHz Tera-Hertz spectrum to the mobile service providers (MSPs) in India in view of achieving high spectrum usage. For a fixed term of renewal (ToR), the formulated DSA technique compares the number of consumers of an MSP with all the remaining MSPs and then assigns the spectrum accordingly. The DSA then updates the assigned spectrum to an MSP at every ToR in accordance with variation in the amount of consumers compared to the previous ToR. The DSA technique is formulated such that it finds the optimal spectrum amount required by every MSP during each ToR. Also, the mean capacity (MC), spectral efficiency (SE), energy efficiency (EE), and cost efficiency (CE) are derived for each MSP. The aforementioned metrics are used to compare the performance of DSA with the static spectrum assignment (SSA) method, which assigns the spectrum to any MSP without accounting for the actual requirement by the consumer. We conduct extensive simulations considering a specific scenario with four MSPs, and the results demonstrate that the DSA technique is able to meet the demands of the 6G wireless systems as it is able to reuse the available spectrum for every MSP for a fewer number of cells of approximately 38% reduced amount of buildings. Further, the results also demonstrate that, in comparison to the traditional static spectrum assignment (SSA) method, DSA improves the MC and SE by 20% and the EE and CE by 25%. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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6. Seismic Response of Multistoried RC Structure with Floating Columns for Different Lateral Load Resisting Systems -- A Comparative Study.
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Swathi K. and Narayana G.
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LATERAL loads , *COLUMNS , *SEISMIC response , *EARTHQUAKE zones , *SHEAR walls , *EFFECT of earthquakes on buildings , *SPECTRUM analysis , *LAMINATED composite beams , *EARTHQUAKE resistant design - Abstract
Soft storeys, floating columns, vertical or plan irregularities, and large loads are common features of modern multi-storey buildings. In metropolitan India, these types of construction have grown increasingly common. According to the findings of previous earthquake research, the majority of the RC structures built with such imperfections are very unpleasant in seismically active places. These effects occurred as a result of a variety of factors, including non-uniform mass distribution, stiffness, and strength. This study explains the seismic analysis of a G+10 multi-storied building resting on floating columns with different lateral load resisting systems such as shear wall and bracings at different locations and comparison between them in seismically active areas observing its responses to the lateral stresses being applied to the structure externally in seismic zone III using the software ETABS. All models are subjected to equivalent static and response spectrum analysis, with result specified as seismic factors such base shear, storey displacement, storey drift and storey shear. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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7. Phosphoric acid treatment enhances adaptation of glass-ionomer cement to bioceramic sealer-conditioned dentin.
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Suresh, Nandini, Chandrasekaran, Sooriaprakas, Ashritha, M. C. V., Raoufe, Mohammed Abdul, Vasudevan, Aishwarya, and Natanasabapathy, Velmurugan
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IN vitro studies ,DENTIN ,PHOSPHORIC acid ,DENTAL materials ,MOLARS ,MANDIBLE ,SCANNING electron microscopy ,X-ray spectroscopy ,DENTAL glass ionomer cements ,ENDODONTICS ,SPECTRUM analysis - Abstract
Background: This study evaluated the interface between fresh eugenol/bioceramic sealer-conditioned coronal dentin and high-viscous glass-ionomer cement (HVGIC), treated with various dentin conditioners (saline, 10% polyacrylic acid, and 37% phosphoric acid). Materials and Methods: Standard endodontic access preparation and instrumentation were done in 21 freshly extracted mandibular molar teeth in this in vitro study. Teeth were divided into two interventional groups (n = 9/group), based on the type of sealer (zinc oxide eugenol [ZOE]/ bioceramic [BioRoot RCS] sealer) used for obturation. Samples were further subdivided based on the type of dentin-conditioning procedures performed (saline/10% polyacrylic acid/37% phosphoric acid). Post dentin conditioning, the access cavity was sealed with HVGIC. Later, material-dentin interfacial analysis and elemental analysis were done using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy. Results: The interfacial SEM images of HVGIC layered over B-RCS/ZOE sealer-conditioned dentin, treated with saline, showed predominantly adhesive debonding failures, whereas cohesive debonding was observed with polyacrylic and phosphoric acid. In the elemental analysis, the intensity of zirconium (depicting the residue of B-RCS)/zinc (depicting ZOE sealer) was very high on the dentin side treated with saline, in comparison to the dentin treated with polyacrylic and phosphoric acid. Furthermore, the intensity of elements from HVGIC was low on the dentin side of the groups with saline, whereas these elements showed maximum penetration into the dentin when treated with phosphoric acid. Conclusion: Conditioning of the endodontic access cavity using 37% phosphoric acid immediately postobturation resulted in higher penetration of HVGIC into the dentin, in comparison to the other dentin conditioners. [ABSTRACT FROM AUTHOR]
- Published
- 2023
8. A review on seismic analysis of tall building (G+10).
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Kukwas, Adit, Khawas, Ritik, Pandey, Vivek, Solanki, Tushar, Naik, Kartik, Dabhekar, Kuldeep, Khedikar, Isha, and Pawar, Neha
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TALL buildings , *BENDING moment , *SPECTRUM analysis , *DESIGN software , *SOFTWARE architecture , *EARTHQUAKE zones - Abstract
Nowadays, in our country earthquake has shown an increase in seismic zoning factor over various parts. India is divided into 4 seismic zones that are seismic zones 2,3,4 and 5, which covers over 60% of total land area. So, it has become very important to decide seismic reactions over structures in these particular risky zones. This review shows different research that has been carried out on this topic to get an overall idea where we stand currently and what more we can do. Comparison of result is done with respect to different parameters like displacement, storey drift, bending moment etc. Authors have used different types of methodologies and modern-day techniques like Response spectrum analysis and Equivalent static method to analyze a good range of structures and their seismicity. This review paper focuses on comparing manual calculations with a long range of advanced designing software data to finally get the optimum conclusion in the field of seismic analysis. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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9. Characterization of suspended microplastics in surface waters of Chalakudy River, Kerala, India.
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Maneesh Kumar, S. K., Kartha, Aswathy R., Rajathy, S., Ratheesh Kumar, C. S., Chandini, P. K., Vidya, P. V., Madhuraj, P. K., Sajith, K. S., and Anamika, S.
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PLASTIC marine debris , *MICROPLASTICS , *RAMAN spectroscopy , *SPECTRUM analysis , *PLASTICS - Abstract
The investigation focused on identification and quantification of microplastics in surface waters of Chalakudy River, Kerala. Microplastics were detected in the surface waters of the study area with a recovery rate of 108.33 mg particles L−1. The abundance of microplastics ranged from 15.13 ± 4.13 – 170 ± 17.75 particles L−1 (mean: 55.81 ± 34 particles L−1). A maximum number of microplastics were obtained from site C3 and the least from site C8. The weight distribution of microplastic on sites exhibited strong positive correlation with the abundance (r = 0.83). Microplastics of size <20 µm were in higher abundance in the study area. Microscopic examination revealed fragments (47.06%) as predominant plastics and the dominant colour was brown/mud (26.99%). Abundance of coloured plastics indicated the probability of damage to aquatic life. Raman spectrum analysis revealed that Low-Density Poly Ethylene (40%) as the predominant polymer that could be observed at all the sampling sites. Lower-sized microplastics would cause accidental ingestion by organisms. The estimated release of a higher average number of microplastic particles (55.81 ± 4.25) into the marine environment is of serious concern. The observed overall abundance and recovery rate of microplastics in the study area indicated the status of contamination due to a multitude of sources. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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10. An Updated Mutation Spectrum of the ?-Secretase Complex: Novel NCSTN Gene Mutation in an Indian Family with Hidradenitis Suppurativa and Acne Conglobata.
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Ratnamala, Uppala, Jain, Nayan K., Jhala, Devendrasinh D., Prasad, Pullabatla V. S., Saiyed, Nazia, Nair, Sreelatha, and Radhakrishna, Uppala
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ACNE , *GENETIC mutation , *PAPER chromatography , *PROTEOLYTIC enzymes , *GENETIC testing , *MEDICAL genetics , *HIDRADENITIS suppurativa , *SPECTRUM analysis , *LONGITUDINAL method - Abstract
Background: Hidradenitis suppurativa (HS) is a complex, chronic inflammatory skin disorder whose pathophysiology is poorly understood. Genetic studies have shown that HS is predisposed by mutations in the γ-secretase gene, but only a proportion of familial and partial sporadic cases have been shown to possess such mutations. HS has high genetic heterogeneity and is thought to be triggered by a combination of genetics and environmental factors. Aims: The study aimed to investigate the genetic causes of HS in a large cohort of patients and to update the mutation spectrum of γ-secretase complex genes. Methods: We conducted mutational screening of 95 sporadic HS cases and one large family with both HS and acne conglobata (AC) to identify mutations in the coding and splice junction region of γ-secretase complex genes (nicastrin (NCSTN), presenilin 1 (PSEN1), presenilin enhancer 2 (PSENEN), and aph-1 homolog B, gamma-secretase subunit (APH1B)). Results: Our study identified a nucleotide substitution of 1876C>T in the NCSTN gene, which caused a stop codon (p. Arg626X) in the affected members of a large family with HS and AC. No pathogenic variants were detected in 95 sporadic cases of HS, indicating there is possible genetic heterogeneity. Conclusion: We report a new family with a nonsense mutation in the NCSTN gene that supports the role of the γ-secretase complex genes in HS with AC. The updated γ-secretase mutation spectrum for HS now includes 78 mutations. [ABSTRACT FROM AUTHOR]
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- 2023
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11. A short note on the natural and anthropogenic variations in the water storage changes at Visakhapatnam, Andhra Pradesh, India.
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Mathews, Gathala Vinod, Rajesh, Rekapalli, and Begum, Shaik Kareemunnisa
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WATER storage , *SOUTHERN oscillation , *SOLAR oscillations , *SPECTRUM analysis ,EL Nino - Abstract
We analyze the periodic and stochastic/random dynamics in the water storage changes at Visakhapatnam, Andhra Pradesh, India. We used time-variable gravity data in terms of Equivalent Water Thickness (EWT) measured from Gravity Recovery and Climate Experiment (GRACE) and GRACE Follow-On satellite missions for the period 2002 to 2021 along with average rainfall data to assess the natural and anthropogenic impacts on water storage changes. We employ Wavelet Spectrum and Singular Spectrum Analysis (SSA) methods to analyze the non-stationary variation of spectral power and principal components. The water storage in the study area shows a significant positive trend with a peak correlation of 0.52 with the rainfall data at a lag of 3 months. The first, second, third, fourth, and fifth principal components depicting the monotonic trend and oscillations together contribute 69.48% to the total water storage changes. The wavelet spectrum of the SSA reconstructed signal from the first four principal components revealed non-stationary annual and 1.3 to 8 years periodicities associated with natural solar and El-Nino Southern Oscillations (ENSO) respectively. The phase plot of the residual signal of ~ 30% variance suggests the random dynamics. Thus the study suggests: (i) an increasing groundwater trend in the study area, (ii) nearly 70% of the water storage changes are linked with natural solar and ENSO variations, and (iii) 30% of water storage changes are with random dynamics possibly linked with anthropogenic activities and catastrophic climatic episodes of shorter duration at Visakhapatnam, Andhra Pradesh, India. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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12. Skin Colonizers and Catheter Associated Blood Stream Infections in Incident Indian Dialysis Patients.
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Agrawal, Varun, Valson, Anna T., Bakthavatchalam, Yamuna Devi, Kakde, Shailesh, Mohapatra, Anjali, David, Vinoi George, Alexander, Suceena, Jacob, Shibu, Jude Prakash, John Antony, Veeraraghavan, Balaji, and Varughese, Santosh
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SKIN diseases , *HOST-bacteria relationships , *CATHETER-related infections , *DISEASE incidence , *METHICILLIN-resistant staphylococcus aureus , *RISK assessment , *MULTIDRUG resistance , *DISEASE prevalence , *NASAL mucosa , *HEMODIALYSIS , *STATISTICAL correlation , *BLOODBORNE infections , *SPECTRUM analysis , *LONGITUDINAL method , *DISEASE risk factors , *DISEASE complications - Abstract
Introduction: Skin colonization is a risk factor for multi-drug resistant (MDR) catheter-associated bloodstream infections (CABSI). This study aimed to determine the prevalence and spectrum of skin colonizing MDR organisms in incident HD patients and their correlation with CABSI. Methods: This single-center prospective cohort study included consecutive adult incident HD patients who underwent tunneled or non-tunneled internal jugular vein HD catheter insertion between June 1, 2017 and October 31, 2017. Nasal, axillary, and exit site swabs were obtained prior to catheter insertion, at 14-21 days, and 28-35 days after catheter insertion. Results: Forty-three patients (69.7% male, 32.5% diabetic) were included and provided baseline swabs, while 29 and 10 patients respectively were available for follow-up swabs. MDR bacterial colonization, MRSA colonization, and MDR gram-negative colonization on the baseline set of swabs were seen in 76.7%, 69.7%, and 9.3% patients respectively. Of the 29 patients with at least two consecutive sets of swabs, 79.3% showed persistent colonization by MDR gram-positive organisms, most commonly by MRSA. Six patients developed a CABSI during the follow-up period (incidence rate 3.7 per 1000 patient days), 83.4% were gram negative, and in only one instance (16.6%) was the bacterial strain identical to that which had previously colonized the skin. Conclusions: Three-fourths of HD patients were colonized by MDR bacteria prior to HD initiation. Despite the majority being persistently colonized by MDR gram-positive organisms, CABSIs were predominantly gram negative. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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13. Spatiotemporal Rainfall Dynamics in Kosi Basin Using Wavelet Analysis.
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Towheed, Aadil and Roshni, Thendiyath
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WAVELETS (Mathematics) ,RAIN gauges ,SPECTRUM analysis ,POWER spectra ,DATA analysis - Abstract
Spatial and temporal analysis of rainfall data were carried out along with wavelet analysis for seven rain gauge sites of Kosi basin, India during the time period from 1985 to 2017. Wavelet spectrum analysis and wavelet coherence analysis were performed to fully characterize the time-frequency rainfall variability of the rain gauge data in these areas. For all the selected gauge stations during the study period, the peak value of the wavelet power spectrum was identified for the 8-16 month band. The results of wavelet spectrum analysis reveal a good correlation of rainfall data in the rain gauge sites lying in the southwest of the Kosi basin. The spectrum analysis also differentiates the wet and dry periods and it was observed that in the majority of the selected sites, a dry period occurred from the year 2005 onwards. This was again confirmed with breakpoint analysis. The wavelet coherence analysis explicit is a good correlation between the rain gauges in the study area. Overall, the variability of the rainfall parameters was more vivid with the wavelet analysis and this can be extended to other climatological parameters. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
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14. Prediction of dominant daily modes of the Indian summer monsoon in the NCEP GFS model.
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Shahi, Namendra Kumar, Rai, Shailendra, Sahai, A. K., and Abhilash, S.
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PRECIPITATION anomalies ,MONSOONS ,SEASONS ,MADDEN-Julian oscillation ,SPECTRUM analysis ,FORECASTING - Abstract
The prediction capability of dominant daily monsoon modes of Indian summer monsoon in the forecast of the Global Forecast System Version 2 (GFSv2) model is scrutinized. The dominant monsoon modes are procured by performing the multichannel singular spectrum analysis (MSSA) on daily precipitation anomalies of the Indian summer monsoon region (60–100°E, Eq.-35°N) during 2001–2014. The observation has one seasonally persistent mode and two intraseasonal oscillations with periods around 42 and 26 days, and the model has correctly simulated these modes. The spatial structure of the phase composites of the precipitation anomalies of the intraseasonal modes of the model is almost similar to the observed spatial pattern with slightly less magnitude of the precipitation anomalies over Western India and the core monsoon zone. The spatial structure of the 26-day mode is similar to the spatial structure of the 42-day mode with less magnitude of the precipitation anomalies all over the study domain. The lead forecast of the model demonstrates the robust predictive skill of intraseasonal modes. The variation of the active and break spells of monsoon precipitation over the Indian subcontinent is captured accurately by the contribution of both intraseasonal modes. The observed eastward and northward propagation features of the Indian summer monsoon have been accurately simulated by the model. The model has weak seasonally persistent signals over Western India, northeast India, and eastern land regions adjacent to the Western Ghats. The seasonally persistent mode shows a strong relationship with the equatorial central Pacific Ocean SSTs and a moderate correlation with the Indian and Atlantic Ocean SSTs. The seasonally persistent mode contributes largely to the seasonal precipitation anomalies over the Indian monsoon region. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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15. Comparison of diagnostic ability of standard automated perimetry, short wavelength automated perimetry, retinal nerve fiber layer thickness analysis and ganglion cell layer thickness analysis in early detection of glaucoma.
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Kalyani, V, Bharucha, Khurshed, Goyal, Nikhil, Deshpande, Madan, Kalyani, V Ks, Bharucha, Khurshed M, and Deshpande, Madan M
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NERVE fibers , *PERIMETRY , *CELL analysis , *SPECTRUM analysis , *GLAUCOMA , *OPTICAL coherence tomography , *GLAUCOMA diagnosis , *NEURONS , *RETINA , *VISUAL fields , *INTRAOCULAR pressure - Abstract
Purpose: The aim of this study was to compare the diagnostic ability of macular ganglion cell layer (GCL) analysis using spectral domain optical coherence tomography against retinal nerve fiber layer analysis (RNFL), short-wavelength automated perimetry (SWAP), and standard automated perimetry (SAP) in early detection of glaucoma.Methods: Participants fulfilling the inclusion criteria were consecutively enrolled from the glaucoma clinic of tertiary care eye hospital in Western India from November 2015 to October 2016. The subjects underwent a detailed evaluation by trained glaucoma specialists. On suspicion of glaucoma, the patients underwent SAP, SWAP, and SD-OCT for GCL and RNFL analysis.Results: There were 91 patients in total of which experts classified 54 eyes into GON and 37 eyes into nonglaucomatous group. Sensitivity of SAP (42.59%) was significantly lower (P < 0.05) than that of average GCL thickness (79.63%) and average RNFL thickness (72.22%). Specificity and positive LR of SWAP (97.3% and 19.19, respectively) and SAP (94.6% and 7.88, respectively) were greater than those of GCL (81.08% and 4.21) and RNFL (67.57% and 2.23) parameters. Negative LR of average GCL thickness (0.25) was superior to that of average RNFL thickness (0.411), SWAP (0.495), and SAP (0.607).Conclusion: Macular GCL parameters perform better than RNFL parameters in patients with early glaucomatous damage. There is superior ability of SWAP over SAP in detecting glaucomatous changes in glaucoma suspect group. GCL thickness analysis has higher sensitivity and negative likelihood ratio, whereas SWAP had higher specificity and positive likelihood ratio. Thus, combining both tests can lead to better diagnostic ability for early glaucomatous damage. [ABSTRACT FROM AUTHOR]- Published
- 2021
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16. Modeling and analysis of ionospheric TEC variability from GPS–TEC measurements using SSA model during 24th solar cycle.
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Dabbakuti, J.R.K. Kumar, Peesapati, Rangababu, Panda, Sampad Kumar, and Thummala, Srinivasarao
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SOLAR cycle , *GLOBAL Positioning System , *STANDARD deviations , *SOLAR activity , *MAGNETIC storms , *SPECTRUM analysis - Abstract
Ionospheric modeling across the Indian low latitudes continues to be a challenging task because of the day-to-day variability pertaining to the underlying complex equatorial and low latitude electrodynamics. In this paper, we aimed at developing an ionospheric Total Electron Content (TEC) model based on Singular Spectrum Analysis (SSA) using the Global Positioning System (GPS)-TEC observations (from 2009 to 2019) at Bengaluru (Geographic: 13.02° N, 77.57° E; Dip Angle: 13.77° N), a low latitude station in India. SSA has the most significant advantage of extracting information from the noisy time-series data with the first-four SSA modes in the decomposition, almost converging to total variance of about 99%. The proposed SSA-TEC model has been assessed by comparing it with the GPS-TEC observations as well as the outcomes from the latest version of the International Reference Ionosphere model (IRI-2016) and International GNSS Services Global Ionosphere Maps (IGS-GIM). The results demonstrate excellent outcomes with the Root Mean Square Error (RMSE) values between observed and model estimations laying at 1.58 TECU (SSA), 7.04 TECU (IRI-2016), and 8.89 TECU (GIM) with the respective correlation coefficients 0.99, 0.91, and 0.94. The model outcomes are in good agreement with the GPS-TEC observations, presenting relatively better estimates of TEC than the IRI-2016 and GIM during the geomagnetically quiet and disturbed daytime and nighttime conditions under different seasons and solar activity. Moreover, the proposed SSA-TEC model replicates the significant changes and time distribution characteristics of the ionosphere over the low latitude location, foreseeing the scopes for its regional implementation with a wide range of operations. • Ionospheric TEC model is proposed based on Singular Spectrum Analysis (SSA). • Model outcomes is assessed by comparing with the GPS-TEC, IRI and GIM estimations. • Excellent model outcomes are achieved with low RMSE and high correlations. • A decent agreement with GPS-TEC is seen even during geomagnetic storm conditions. • The outcomes suggest a regional model implementation for near-realtime operations. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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17. Framework for demystifying M2M spectrum regulation
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Bhakthavatsalam, Anuradha C and Khosla, Arpit
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- 2018
18. Standoff femtosecond filament-induced breakdown spectroscopy for classification of geological materials.
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Abdul Kalam, S., Balaji Manasa Rao, S. V., Jayananda, M., and Venugopal Rao, S.
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LASER-induced breakdown spectroscopy , *RADIANT intensity , *CLASSIFICATION , *TRACE elements , *SPECTRAL lines , *SPECTRUM analysis - Abstract
Femtosecond (fs) filaments delivering substantial peak intensities at remote locations are being exploited in several practical applications together with in situ remote/standoff (ST) investigations. The optical emissions produced during the filament interaction were analyzed to study the composition of distant targets. In this article, we present the comparative results obtained from qualitative studies of territorial rocks (collected from the central Dharwar craton, South India) in the near-field and in the standoff mode with fs laser induced breakdown spectroscopy (fs LIBS) and fs filament induced breakdown spectroscopy (fs FIBS) techniques. The granitoids possessing distinct mineralogical and chemical characteristics were analyzed in their original form in ambient air from a distance of (i) ∼15 cm with tightly focused fs pulses in near-field configuration and (ii) ∼6.5 m using fs filaments in standoff configuration. Various atomic emission lines belonging to major elements such as Ca, K, Na, Al, Fe and Mg were identified and labelled from both fs LIBS and fs FIBS spectra of each sample. Few spectral lines corresponding to trace elements such as Ba, Ti and V were also identified. Furthermore, Mg/Ca, Fe/Ca, Mg/Al, Ca/Al, Mg/Si and Fe/Si ratios were considered to highlight the differences that could serve for the classification of these granitoids. A good correlation of constituent element spectral line intensities, especially in the standoff mode, was observed with weight percentage of their oxides obtained from X-ray fluorescence (XRF) data. The overall change in relative standard deviation (RSD%) of major spectral intensities for a sample was observed to be lower (5–25%) in the standoff case in comparison to that of the near-field configuration (16–38%). Furthermore, the results from the principal component analysis (PCA) employed in tandem with normalized/unnormalized fs ST-FIBS data of these geological rock samples demonstrated a high degree of qualitative classification in comparison to normalized/unnormalized fs LIBS data. Therefore, we firmly believe that the results from the present work clearly extend the application of fs filaments to standoff analysis of geological beds and mineral ores under the ambient atmospheric conditions intended for unpleasant environment detection. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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19. Extraction of Nonlinear Trends in Time Series of Rainfall Using Singular Spectrum Analysis.
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Aswathaiah, Usha and Nandagiri, Lakshman
- Subjects
TIME series analysis ,RAINFALL ,SPECTRUM analysis ,HYDRAULIC structures ,WATERSHEDS ,STREAM-gauging stations ,CLIMATE change - Abstract
Characterization of nonlinear trends in time series of hydroclimatic variables exhibiting nonstationarity is necessary for more realistic projections of climate change and for optimal design of hydraulic structures. The present study was conducted to demonstrate the applicability of a novel Monte-Carlo-based singular spectrum analysis (SSA) to characterize nonlinear trends in historical time series of rainfall characteristics. Long-term (1960–2015) rainfall records for 17 gauges located in the Malaprabha River Basin, India, were used to analyze spatiotemporal variabilities of trends in rainfall totals and number of rainy days for annual and seasonal time periods. While the traditional Sen's Slope and Mann–Kendall (MK) trend tests indicated statistically nonsignificant decreasing monotonic trends at most gauge stations, SSA revealed the existence of steep nonlinear trends and distinct change points in the direction of the trend over the period of record for both rainfall and rainy days. Results of this study demonstrate the potential for SSA to extract crucial information on the trajectories of nonlinear trends and change points in time series of hydroclimatic variables that exhibit nonstationarity. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
20. The fidelity of a regional coupled model in capturing the relationship between intraseasonal variability and the onset/demise of the Indian summer monsoon.
- Author
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Karmakar, Nirupam and Misra, Vasubandhu
- Subjects
- *
MONSOONS , *MADDEN-Julian oscillation , *LOYALTY , *SPECTRUM analysis , *SUMMER , *RAIN gauges - Abstract
Onset and demise of the Indian summer monsoon (ISM) and intraseasonal variability (ISV) embedded within the ISM are dominant climatological phenomena observed over the Indian region. In this study, a quantitative relationship between these two phenomena is assessed and the performance of a regional coupled model in simulating the relationship in the ISM is examined. An objective definition of the local onset and demise of the ISM is used based on more than a century-long India Meteorological Department rain-gauge observation and 10-year-long model simulated precipitation. Two distinct modes of intraseasonal oscillations (ISOs), northwestward propagating 10–20-day periodic high-frequency ISO and northward moving 20–70-day periodic low-frequency ISOs are extracted using Multichannel Singular Spectrum Analysis (MSSA). It is found that nearly 60% of the local onset of the ISM occurs during the positive developing phases of the ISO; whereas, a similar fraction of local demise occurs during positive decaying phases of the ISO across almost entire India. Essentially, the phase-locking of two ISOs creates the most conducive environment for onset or demise of the ISM to occur. In this study we found that the model not only captures the overall structure of the ISO modes, but also simulates the observed distribution of the onset and demise dates of ISM in different ISO phases. The diagnostics described here, with the ability of the model to produce the observed phenomena, provide an essential tool to improve our understanding of the monsoon system and its predictability. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
21. Design & development of nanosponge loaded topical gel of curcumin and caffeine mixture for augmented treatment of psoriasis.
- Author
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Iriventi, Padmini, Gupta, N. Vishal, Osmani, Riyaz Ali M., and Balamuralidhara, V.
- Subjects
- *
PSORIASIS , *ANIMAL experimentation , *CURCUMIN , *DRUG design , *PHARMACEUTICAL gels , *CAFFEINE , *POLYMERS , *CUTANEOUS therapeutics , *NANOMEDICINE , *PHARMACEUTICAL chemistry , *MICE , *SPECTRUM analysis - Abstract
Background: Combination of curcumin with anti-inflammatory drug like caffeine shows augmented antipsoriatic action compared to curcumin alone and reduce the time taken for treatment of Psoriasis. Objective: The objective of the present study was to develop nanosponge (NS) based topical gel of curcumin (CUR) and caffeine (CFN) combination that acts as a potential system for the treatment of psoriasis. Methods: NS composed of dimethyl carbonate (DMC) as crosslinker and beta-cyclodextrin (β-CD) as polymer were prepared by hot melt method and incorporated in topical gels. Factorial design (32) was constructed in a fully randomized manner to study all nine possible experimental runs. The gels were prepared by varying the content of carbopol-934 (gelling agent) (X1) and guar gum (polymer) (X2). The effect of these two independent variables on viscosity (Y1) and in vitro percent drug release (Y2) of prepared gels was evaluated. Other evaluation studies for NS and nanogels were conducted. In vivo animal studies were carried out for optimized formulation using mouse model of imiquimod-induced psoriasis. Results: The physical and chemical characteristics exhibited by the prepared NS and gels (F1-F9) were found to be optimal. The optimization resulted in achieving formulation N10 with 69.72% in vitro drug release and 12,329.78cp viscosity. Histopathology studies revealed that prepared nanogel has promising anti-psoriatic activity. The results concluded that CUR and CFN combination has reduced the time required for showing anti-psoriatic activity to 10 days when compared to CUR alone that took around 20 days. Moreover, the nanogel has depicted sustained drug release till 12 h. Conclusions: From the experimental findings it has been concluded that CUR and CFN combination significantly augmented the anti-psoriatic efficacy with respect to individual components and also reduced the time required for onset of effect. Thus, the proposed nanogel would be an imperative drug delivery system for more effective anti-psoriatic therapy. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
22. Influence of global sea‐surface temperature on ultra‐low‐frequency variability in Indian summer monsoon rainfall.
- Author
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Karmakar, Nirupam, Chakraborty, Arindam, and Nanjundiah, Ravi S.
- Subjects
- *
RAINFALL , *SURFACE pressure , *TEMPERATURE , *DROUGHTS , *SPECTRUM analysis , *CYCLOGENESIS , *TRAFFIC violations , *QUASI-biennial oscillation (Meteorology) - Abstract
A multidecadal or ultra‐low‐frequency mode of variability in Indian summer monsoon rainfall (ISMR) with a spectral peak at nearly 67 years is identified using a nonparametric approach, namely, singular spectrum analysis. Not only does this mode modulate the seasonal mean rainfall over India, but also frequent occurrences of excess or below normal rainfall over India are favored by the phases of this mode. We show that 80% of all droughts occur during the negative phase of this mode, compared with 60% of all floods during its positive phase. Although the existence of this mode was reported in many previous studies, proper understanding of its exact nature and driving mechanism, and how it relates to global sea‐surface temperature (SST), is still not clear. Here, we show that the 67‐year variability in ISMR is associated with a SST mode of similar periodicity, which primarily exhibits a hemispheric SST difference, with the strongest signals over the northern Pacific and Atlantic. The positive phase of this SST mode induces low surface pressure over the northern Arabian Sea. Changes in surface pressure over the northern Arabian Sea govern changes in ISMR. The bridge between the SST mode and central Asian circulation is possibly established through the North Pacific Oscillation. The positive phase of this mode enhances the meridional temperature gradient over India, which acts to strengthen the tropical easterly jet, and subsequently the low‐level westerly jet over India. These lead to a negative surface pressure anomaly over the Indian subcontinent and an associated anomalous cyclonic circulation. The environment thus created is conducive to increased seasonal mean monsoon rainfall over India. The phase of the SST mode is remarkably similar to, and leading by 2–3 years, that of the multidecadal mode in ISMR up to the 1990s. However, the relationship weakens after the early 1990s. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
23. Broadband reflectance, emittance spectroscopy and self-potential geophysical survey for targeting gold sulphide lode deposit in Bhukia, Rajasthan, India.
- Author
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Rani, Komal, Guha, Arindam, Pal, Sanjit Kumar, and Kumar, K. Vinod
- Subjects
- *
GEOPHYSICAL surveys , *REFLECTANCE , *SULFIDES , *SPECTRUM analysis , *IMAGE registration - Abstract
In this study, we have analyzed the comparative potential of reflectance and emittance bands of advanced spaceborne thermal emission and reflection radiometer (ASTER) sensor for detecting surface exposures of Proterozoic rocks and gossan capping of gold mineralization. In this regard, few new image analysis products are derived. These are matched filtering factor-modified ratio (MFR) image and the inverse of a difference image of the ratio and matched filtering map (IDRM). These image products are used with the conventional ratio images, relative band depth images and index-based principal component (PC) images of reflectance and emittance bands of ASTER for delineating metasediments of the study area. We have found that reflectance band products are superior for mapping metasediments and gossan capping than the emissivity products, which are only suitable to enhance quartzite. Self-potential (SP) geophysical survey is carried out around the identified gossan site as SP is sensitive to sulphide mineralization. Results of the SP survey indicated presence of sulphide enrichment underneath the gossan. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
24. A FOOD SPECTRUM ANALYSIS OF THREE BUFONID SPECIES (ALMURA: BUFONIDAE) FROM UTTARAKHAND REGION OF THE WESTERN HIMALAYA, INDIA.
- Author
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Bahuguna, Vivekanand, Chowdhary, Ashish Kumar, Singh, Shurveer, Bhatt, Gaurav, Bhardwaj, Siddhant, Lohani, Nikita, and Bahuguna, Satyanand
- Subjects
FOOD chemistry ,SPECTRUM analysis ,BUFONIDAE ,SPECIES ,INSECT diversity ,AMPHIBIANS - Abstract
The ecological diversity of insects and its predators like amphibians are important determinants in ecological balance. A total of 1,222 prey items in 84 specimens were examined to contribute the understanding of the diets of three Duttaphrynus species, viz., himalayanus, melanostictus, and stomaticus from Uttarakhand, the western Himalaya, India. Gut content analysis of three bufonids revealed acceptance of a wide range of terrestrial insects and other invertebrates as their food. The index of relative importance indicated that the most important preys were Formicidae, Coleoptera and Orthoptera. Duttaphrynus melanostictus had the broadest dietary niche breadth, followed by D. himalaynus and D. stomaticus. The wide prey spectrum well indicates that these species are the generalist and opportunist invertebrate feeder. Information pertaining to the food spectrum analysis contributes to understanding the ecological roles and used as a baseline data for future successful amphibian conservation and management programs in the Himalayan ecosystem. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
25. Elemental Composition of Betel Leaves Using a Novel Optical Spectroscopic Technique.
- Author
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Edith A KA, Ongole R, V K U, U K A, and N R N
- Subjects
- Humans, India, Spectrum Analysis, Calcium, Dietary, Calcium, Copper
- Abstract
Objective: Assess trace elements in betel leaves and slaked lime from different regions of Karnataka, India using Laser Induced Breakdown Spectroscopy (LIBS). Materials and Method: Betel leaves from six different regions of Karnataka were obtained and named (for the purpose of the study) BL1, BL2, BL3, BL4, BL5, and BL6 and they were sun-dried. A single tube of slaked lime was obtained from the local ‘paan’ shop. Each dried leaf and a single blob of slaked lime was subjected to elemental analysis using Laser-induced breakdown spectroscopy. Results: A ten-trial experiment was carried out in all six leaves and a blob of the slaked lime. The National Institute of Standards and Technology (NIST) database was used to assess the emission lines. The elements that were predominantly present in all six betel leaves from different regions of Karnataka are calcium, copper, and iron. Slaked lime showed only the presence of calcium. Conclusion: It is widely accepted that the consumption of betel quid causes various changes in the oral mucosa including oral potentially malignant disorders (OPMDs) and oral cancer. It is important to analyze each component of betel quid to understand the disease progression. Copper is found to be relatively higher in betel leaves, and it is known that copper-induced fibrogenesis via the lysyl oxidase pathway in oral submucous fibrosis.
- Published
- 2023
- Full Text
- View/download PDF
26. Non-parametric characterization of long-term rainfall time series.
- Author
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Tiwari, Harinarayan and Pandey, Brij Kishor
- Subjects
TIME series analysis ,TREND analysis ,RAINFALL ,LINEAR statistical models ,SPECTRUM analysis ,SYSTEMS design - Abstract
The statistical study of rainfall time series is one of the approaches for efficient hydrological system design. Identifying, and characterizing long-term rainfall time series could aid in improving hydrological systems forecasting. In the present study, eventual statistics was applied for the long-term (1851–2006) rainfall time series under seven meteorological regions of India. Linear trend analysis was carried out using Mann–Kendall test for the observed rainfall series. The observed trend using the above-mentioned approach has been ascertained using the innovative trend analysis method. Innovative trend analysis has been found to be a strong tool to detect the general trend of rainfall time series. Sequential Mann–Kendall test has also been carried out to examine nonlinear trends of the series. The partial sum of cumulative deviation test is also found to be suitable to detect the nonlinear trend. Innovative trend analysis, sequential Mann–Kendall test and partial cumulative deviation test have potential to detect the general as well as nonlinear trend for the rainfall time series. Annual rainfall analysis suggests that the maximum changes in mean rainfall is 11.53% for West Peninsular India, whereas the maximum fall in mean rainfall is 7.8% for the North Mountainous Indian region. The innovative trend analysis method is also capable of finding the number of change point available in the time series. Additionally, we have performed von Neumann ratio test and cumulative deviation test to estimate the departure from homogeneity. Singular spectrum analysis has been applied in this study to evaluate the order of departure from homogeneity in the rainfall time series. Monsoon season (JS) of North Mountainous India and West Peninsular India zones has higher departure from homogeneity and singular spectrum analysis shows the results to be in coherence with the same. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
27. Research from Tamil Nadu Has Provided New Study Findings on Autism Spectrum Disorders (An In-Depth Analysis of Autism Spectrum Disorder Using Optimized Deep Recurrent Neural Network).
- Subjects
AUTISM spectrum disorders ,RECURRENT neural networks ,SPECTRUM analysis ,FEATURE extraction ,COMMUNICATIVE competence ,COST control - Abstract
A recent study conducted in Tamil Nadu, India, has focused on autism spectrum disorders (ASD) and their impact on behavior and communication abilities. The study highlights the increasing number of people being diagnosed with ASD and the high medical expenses associated with it. To address these challenges, the researchers propose a novel deep recurrent neural network algorithm for the detection of autism levels. The algorithm utilizes an artificial algae algorithm for feature extraction and an intelligent water droplet algorithm for obtaining optimal weights and biases. The experimental results show promising classification accuracy, sensitivity, and cost reduction. For more information, readers can refer to the research article published in the International Journal of Uncertainty, Fuzziness and Knowledge-Based Systems. [Extracted from the article]
- Published
- 2023
28. Development of Software for Automatic Analysis of Intervention in the Field of Homeopathy.
- Author
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Jain, Rajesh Kumar, Goyal, Shagun, Bhat, Sushma N., Rao, Srinath, Sakthidharan, Vivek, Kumar, Prasanna, Sajan, Kannanaikal Rappayi, Jindal, Sameer Kumar, and Jindal, Ghanshyam D.
- Subjects
- *
DRUG monitoring , *ALGORITHMS , *AUTOMATION , *BLOOD flow measurement , *GRAPHICAL user interfaces , *HEART beat , *HEMODYNAMICS , *HOMEOPATHIC agents , *RESEARCH funding , *SPECTRUM analysis , *SOFTWARE architecture , *STROKE volume (Cardiac output) , *PHARMACODYNAMICS , *EQUIPMENT & supplies - Abstract
To study the effect of homeopathic medicines (in higher potencies) in normal subjects, Peripheral Pulse Analyzer (PPA) has been used to record physiologic variability parameters before and after administration of the medicine/placebo in 210 normal subjects.Objective: Data have been acquired in seven rounds; placebo was administered in rounds 1 and 2 and medicine in potencies 6, 30, 200, 1 M, and 10 M was administered in rounds 3 to 7, respectively. Five different medicines in the said potencies were given to a group of around 40 subjects each. Although processing of data required human intervention, a software application has been developed to analyze the processed data and detect the response to eliminate the undue delay as well as human bias in subjective analysis. This utility named Automatic Analysis of Intervention in the Field of Homeopathy is run on the processed PPA data and the outcome has been compared with the manual analysis. The application software uses adaptive threshold based on statistics for detecting responses in contrast to fixed threshold used in manual analysis.Methods: The automatic analysis has detected 12.96% higher responses than subjective analysis. Higher response rates have been manually verified to be true positive. This indicates robustness of the application software. The automatic analysis software was run on another set of pulse harmonic parameters derived from the same data set to study cardiovascular susceptibility and 385 responses were detected in contrast to 272 of variability parameters. It was observed that 65% of the subjects, eliciting response, were common.Results: This not only validates the software utility for giving consistent yield but also reveals the certainty of the response. This development may lead to electronic proving of homeopathic medicines (e-proving). [ABSTRACT FROM AUTHOR]Conclusion: - Published
- 2018
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- View/download PDF
29. Retrospective Analysis of Spectrum of Presentation and Treatment Outcome in Extremity Sarcomas: A Single-Centre Experience.
- Author
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Bansal, Saurabh, Das, Kunal, Jain, Navneet, Nautiyal, Vipul, Gupta, Meenu, Shirazi, Nadia, Verma, Sanjiv, Ahmad, Mushtaq, and Saini, Sunil
- Subjects
- *
CANCER treatment , *AMPUTATION , *ADJUVANT treatment of cancer , *EXTREMITIES (Anatomy) , *LUNGS , *METASTASIS , *SARCOMA , *SPECTRUM analysis , *SURVIVAL , *TREATMENT effectiveness , *RETROSPECTIVE studies , *CHEMORADIOTHERAPY , *PROGNOSIS - Abstract
Introduction . The most common site for soft tissue sarcoma is extremity. As complete surgical resection is possible in majority, outcome of this subset is relatively better. There is paucity of data regarding extremity soft tissue sarcoma (STS) from sub-Himalayan and hilly geographical regions.Materials and Methods . Retrospective analysis was done for extremity STS visiting the study center over a period of 5 years. Data were collected and analyzed for demography, disease characteristics, treatment modalities, and outcome.Result . Extremity STS constituted 32.8% of all STS enlisted. Most common subtype noted was pleomorphic STS. Metastatic disease at presentation was noted among 7/43 cases with lung being the most common metastasis site. Wide local excision was done in 37 cases while amputation was required in 5 cases. Adjuvant radiotherapy was given in 27 cases while 18 cases received adjuvant chemotherapy. At median follow-up of 47 months, the overall survival and event-free survival were noted as 47.64% and 41.49%, respectively.Conclusion . This study depicts single-center experience of extremity STS. The population analyzed was from sub-Himalayan region with significant lost to follow-up. Pooling of data from different centers has been advocated to derive conclusive results. [ABSTRACT FROM AUTHOR]- Published
- 2018
- Full Text
- View/download PDF
30. Carcinoma of the tongue in renal transplant recipients: An unusual spectrum of de novo malignancy at a tertiary care center in India over a period of 26 years.
- Author
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Narayan, G, Jha, R, Srikant, P, Sinha, S, Swarnalata, G, and Raju, K. V. V. N
- Subjects
- *
LIVER tumors , *LUNG tumors , *SKIN tumors , *LYMPHOPROLIFERATIVE disorders , *RAPAMYCIN , *MOUTH tumors , *COLON tumors , *CELL receptors , *ENZYME inhibitors , *FISHER exact test , *IMMUNOSUPPRESSION , *KIDNEY transplantation , *ORGAN donors , *SPECTRUM analysis , *TRANSPLANTATION of organs, tissues, etc. , *TUMORS , *TREATMENT effectiveness , *EARLY diagnosis , *TERTIARY care , *DIAGNOSIS ,TONGUE tumors - Abstract
Renal transplant recipients are at a higher risk of malignancy. We report our experience and the critical differences in the presentation of malignancy in kidney transplant patients performed at our tertiary care center and followed up over the period of 1990–2015. A total of 338 live donor transplants performed in 332 patients were analyzed. Induction immunosuppression was used in 22 cases with interleukin-2 (IL-2) receptor antibody. Overall 299 patients were continued on calcineurin inhibitor (CNI)-based triple drug immunosuppression, 33 were off CNI with 13 of them receiving sirolimus additionally. A total of 16 malignancies including post transplant lymphoproliferative disease (5), oral cancer (5), lung cancer (2), hepatobiliary cancer (2), colon cancer (1), and skin cancer (1) were diagnosed in 15 patients. Over the 26-year follow up, 138 patients died of whom 12 died due to cancer. Cancer occurred in 4.7% of patients but accounted for 9.4% of deaths. Oral cancer occurred after a significantly longer latency of over 10 years (212 vs. 94 months, P = 0.00652). Despite the longer latency, oral cancer patients were younger at diagnosis (44.0 vs. 52 years, P = 0.01016) and had better outcome (Fisher's exact test, P = 0.0275). This was despite a longer overall follow-up for the oral cancer patients, reflecting the better outcome for these patients (24 vs. 4 months, P = 0.0278). This might be the result of relatively early diagnosis of oral cancers. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
31. Site classification for strong motion stations in Gujarat, India using response spectral ratio.
- Author
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Choudhury, Pallabee, Chopra, Sumer, and Roy, Ketan Singha
- Subjects
- *
SEISMIC response , *EARTHQUAKES , *SEDIMENTARY basins , *SEISMIC waves , *SPECTRUM analysis - Abstract
We propose a site classification scheme of strong motion sites of Gujarat, India based on predominant period estimated from 5% damped mean H/V response spectral ratio following the site classification scheme of Di Alessandro et al. [1] which is an extended scheme of Zhao et al. [2] . The 23 strong motion sites in Gujarat were classified into seven classes based on predominant period of the sites. A total of 388 strong motion records from 223 earthquakes varying in magnitude between 2.5 and 5.6 are utilized for classification of the sites. Most of the records are from local earthquakes with hypocentral distance less than 50 km. Previous attempts to classify sites based on local site conditions and geology could not incarcerate the site characteristics and variability within the same geological conditions. The presented site characterization methodology is quick and inexpensive where for instance; sites with thick sedimentary column like basins can be identified quickly without invasive analysis. Also, this classification based on predominant period, which contains both velocity and thickness of resonant layers in its definition, is better than site classification based on Vs30 criteria which captures the site response for only 30 m. The site effects captured in this classification scheme can be utilized in the ground motion prediction equations developed for the region. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
32. Spectrum of acute poisoning: A retrospective observational study in a tertiary care hospital in North India.
- Author
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Kaur, Sharminder, Gupta, Sapna, Sadiq, Shamiya, and Khajuria, Vijay
- Subjects
ALUMINUM compounds ,DISEASE complications ,SCIENTIFIC observation ,ORGANOPHOSPHORUS compounds ,PESTICIDES ,SPECTRUM analysis ,TREATMENT effectiveness ,RETROSPECTIVE studies ,TERTIARY care - Abstract
The article examines the spectrum of acute poisoning in a tertiary care hospital located in the northern region of India. Incidence of poisoning was found to be more in men as compared with women. The authors concluded that organophosphorous is a common type of poisoning and aluminum phosphide resulted in most of the deaths.
- Published
- 2016
- Full Text
- View/download PDF
33. Effect of Ambient Noise on Pure Tone Hearing Screening Test Conducted in Indian Rural Locations.
- Author
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Abraham, Ajish K., Jain, Chandni, and Yashaswini L.
- Subjects
HEARING disorder diagnosis ,AUDIOMETRY ,NOISE ,RESEARCH funding ,RURAL conditions ,SPECTRUM analysis - Abstract
Pure tone hearing screening test is the most widely used method for detecting hearing impairment. To avoid false positive results, the test needs to be conducted in a quiet environment with ambient noise levels lesser than the maximum permissible noise levels specified by ANSI. Such an environment is not available in the rural areas of India. As per census 2011, 49% of the persons with hearing impairment in India live in rural areas, which emphasize the need to conduct hearing screening in rural locations. No attempts have been made yet to document the ambient noise levels in these rural locations and to find out how these noise levels influence the test results. The present study was an effort to measure the ambient noise levels in three of such locations and to find the effect of these noise levels on the outcome of the hearing screening test conducted on 15 participants at each of these locations. The selected locations were found to have average ambient noise levels of 58.3, 60.1 and 64.8 dBSPL, which were higher than the ambient noise levels reported in the previous studies. Results showed very low specificity at 500Hz test frequency at all the three locations when the pass criterion was 25 dBHL while it was 80% when the pass criterion was 30 dBHL. 100% specificity was observed at all other test frequencies, at all the three locations. Outcome of the study will help to precisely organize hearing screening programs in Indian rural areas. [ABSTRACT FROM AUTHOR]
- Published
- 2016
34. Lead Content of Sindoor, a Hindu Religious Powder and Cosmetic: New Jersey and India, 2014-2015.
- Author
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Shah, Manthan P., Shendell, Derek G., Strickland, Pamela Ohman, Bogden, John D., Kemp, Francis W., and Halperin, William
- Subjects
- *
POWDERS , *RED lead , *LEAD poisoning in children , *HINDUS , *RELIGIOUS articles , *WOMEN in Hinduism , *COGNITION disorders in children , *LEAD analysis , *COMMERCIAL product evaluation , *COSMETICS , *RITES & ceremonies , *SPECTRUM analysis , *DESCRIPTIVE statistics - Abstract
Objectives: To assess the extent of lead content of sindoor, a powder used by Hindus for religious and cultural purposes, which has been linked to childhood lead poisoning when inadvertently ingested. Methods: We purchased 95 samples of sindoor from 66 South Asian stores in New Jersey and 23 samples from India and analyzed samples with atomic absorption spectrophotometry methods for lead. Results: Analysis determined that 79 (83.2%) sindoor samples purchased in the United States and 18 (78.3%) samples purchased in India contained 1.0 ormoremicrograms of lead per gram of powder. ForUS samples, geometric mean concentration was 5.4micrograms per gramcompared with 28.1microgramsper gram for Indiasamples. Themaximumlead content detected in both US and India samples was more than 300 000 micrograms per gram. Of the examined USsindoor samples,19%containedmore than 20micrograms per gram of lead (US Food and Drug Administration [FDA] limit); 43% of the India samples exceeded this limit. Conclusions: Results suggested continued need for lead monitoring in sindoor in the United States and in sindoor carried into the United States by travelers from India, despite FDA warnings. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
35. Indian experts develop new way for colon cancer early detection.
- Subjects
COLON tumors ,EARLY detection of cancer ,SPECTRUM analysis - Abstract
The article reports that the Indian scientists developed a new way that helps detect small pouches lined with sugar molecules which are secreted by cancerous cells that may assist in detection of colon most cancers and its early stage analysis.
- Published
- 2022
36. Anti-migraine effect of Areca Catechu L. nut extract in bradykinin-induced plasma protein extravasation and vocalization in rats.
- Author
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Bhandare, Amol M., Vyawahare, Neeraj S., and Kshirsagar, Ajay D.
- Subjects
- *
MIGRAINE prevention , *MEDICINAL plants , *ALTERNATIVE medicine , *ANIMAL communication , *ANIMAL experimentation , *BIOPHYSICS , *RESEARCH methodology , *ORAL drug administration , *PROBABILITY theory , *RATS , *SPECTRUM analysis , *SUMATRIPTAN , *PLANT extracts , *STATISTICAL significance , *DESCRIPTIVE statistics - Abstract
Ethnopharmacological relevance Areca catechu Linn. (Arecaceae) nut is a popular folk remedy for the treatment of migraine in Kerala and Tamil Nadu states of India. Aim of the study This study was designed to investigate the effect of hydroalcoholic extract of A. catechu L. nut (ANE) treatment on migraine pain in rat models to strengthen its use as an anti-migraine therapy. Materials and methods Bradykinin (0.1 μmol/kg) injection in to left femoral vein of rat produced PPE which was measured with luminescence spectrometer. Vocalizations were produced in rats with 10 μg of bradykinin infusion into common carotid artery. Phonogram was recorded before, during and for 5 min after bradykinin injection and sumatriptan was used as a standard anti-migraine drug. In both models, the ANE was orally administered at doses of 250 and 500 mg/kg, 60 min before bradykinin infusion. Results The PPE was reduced in both ANE treated groups of rats. The percent fluorescein was significantly increased in positive control group (97.00±1.7%; p <0.0001) compared to negative control (63.87±1.2%). With ANE treatments (250 and 500 mg/kg) PPE was significantly decreased to 88.88±1.4% ( p <0.01) and 83.55±0.1% ( p <0.0001) compared to positive control group, respectively. On the other hand in the model of vocalization, with 250 and 500 mg/kg ANE treatment, vocalization was significantly reduced to 33.33% and 16.66%, respectively, compared to saline treated rats. The reduction in vocalization is comparable to the reference drug sumatriptan. Conclusion The findings provide the strong evidence for anti-migraine potential of ANE in rat models of migraine. In summary, therapeutic intervention with ANE treatment could be a promising strategy for prevention of migraine. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
37. Aerosol optical properties over marine and continental sites of India during pre-monsoon season.
- Author
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Patel, Piyush and Shukla, A. K.
- Subjects
- *
AEROSOLS , *MONSOONS , *SPECTRUM analysis , *ERROR analysis in mathematics - Abstract
Ground and satellite based measurements of spectral optical properties of aerosols have been carried out at Dehradun (DDN) in the Indo-Gangetic Plain (IGP) and Kavaratti (KVT) at Lakshadweep in southern Arabian Sea during pre-monsoon season (March-May) 2012. The measurements illustrate distinct seasonal impact on aerosol properties with maximum dust loading during May in conjunction with anthropogenic aerosols over DDN and marine aerosols over KVT. Aerosol optical depth (AOD) values have been observed maximum in May (0.72 ± 0.03) over DDN and in April (0.77 ± 0.05) over KVT. The high AOD at DDN during May is associated with low α and high β, means higher loading in May is associated with coarse mode aerosols, may be dust loading as evident from SSA and volume size distribution. Similarly, high AOD at KVT during March and April are associated with high α and low β, may be due to anthropogenic influence as evident from BT analysis as well as SSA and volume size distribution. However, influence of marine aerosols is also noticeable over KVT during May as indicated by the lower values of α with high turbidity coefficient β. Comparison between sunphotometer and MODIS AOD observations indicates good statistical agreement with the minimal error. [ABSTRACT FROM AUTHOR]
- Published
- 2015
38. Annual Periodicity in the Seismicity and Water Levels of the Koyna and Warna Reservoirs, Western India: A Singular Spectrum Analysis.
- Author
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Yadav, Amrita, Gahalaut, Kalpna, Mallika, K., and Rao, N. Purnachandra
- Subjects
SEISMIC waves ,WATER levels ,RESERVOIRS ,SPECTRUM analysis ,ANALYSIS of variance - Abstract
Association of earthquakes with dams and reservoirs has been reported in several cases worldwide. The Koyna region in western India is one such famous example where earthquakes continue to occur even after 50 years of reservoir impoundment and after the 1967 Koyna earthquake (M 6.3), the largest reported earthquake associated with a reservoir. We analyzed the seismicity data from January 2005 to June 2012 in the Koyna-Wama region as recorded by a local seismic network. We performed a singular spectrum analysis, which shows that water level series has dominance of variance for annual periodicity. For the earthquake time series, a particular zone of earthquakes located close to the Warna reservoir shows predominance of annual frequency, suggesting a compelling relation between seismicity of this zone and reservoir water level changes. The lower-order periodicities in the earthquake time series suggest that additional processes (other than reservoir water level changes, which are not well understood and hence need further investigations) also contribute to earthquake activity throughout the year. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
39. Evidence for Nonlinear Coupling of Solar and ENSO Signals in Indian Temperatures During the Past Century.
- Author
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Tiwari, R., Rajesh, Rekapalli, and Padmavathi, B.
- Subjects
METEOROLOGY ,SEASONAL temperature variations ,SOLAR cycle ,SPECTRAL energy distribution ,NONLINEAR analysis ,SPECTRUM analysis ,PRINCIPAL components analysis ,EL Nino - Abstract
Significant fluctuations have been observed in Indian temperatures during past century. In order to identify the statistical periodicities in the maximum and minimum temperature data of different Indian zones, we have spectrally and statistically analyzed the homogeneous regional temperature series from the Western Himalayas, the Northern West, the North Central, the North East (NE), the West Coast, the East Coast, and the Interior Peninsula for the period of 107 years spanning over 1901-2007 using the multitaper method (MTM) and singular spectrum analysis (SSA) methods. The first SSA reconstructed the principal component of all the data sets representing a nonlinear trend (indicating a monotonic rise in temperature probably due to greenhouse gases and other forcing) that varies from region to region. We have reconstructed the temperature time series using the second to tenth oscillatory principal components of all the eight regions and computed their power spectral density using MTM. Our analyses indicate that there is a strong spectral power in the period range of 2-7 years and 53 years, which are matched respectively with the known El Niño-Southern oscillation (ENSO) periods and ocean circulation cycles. Further, the spectral analysis also revealed a statistically significant but riven cycle in a period range of 9.8-13 years corresponding to the Schwabe cycle in all Indiaian maximum and minimum temperature records and almost all the zonal records except in the NE data. In some of the cases, the 22 year double sunspot (Hale cycle) cycle was also identified here. Invariably the splitting of spectral peaks corresponding to solar signal indicated nonlinear characteristics of the data and; therefore, even small variations in the solar output may help in catalyzing the coupled El Niño-atmospheric ENSO cycles by altering the solar heat input to the oceans. We, therefore, conclude that the Indian temperature variability is probably driven by the nonlinear coupling of ENSO and solar activity. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
40. Determination of Chemical Compositions on Adult Kidney Stones—A Spectroscopic Study.
- Author
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Raju, K. and Rakkappan, C.
- Subjects
- *
KIDNEY stones , *SPECTRUM analysis , *X-ray diffraction , *GENDER , *PATIENTS , *MEDICAL schools - Abstract
The chemical compositions of the kidney stones of both the sexes of patients, aged from 40 to 70, living in and around Chidambaram town are determined by using FT-IR and X-RD technique. The kidney stone samples used in the present study were procured from the Rajah Muthiah Medical College and Hospital, Annamalai University. The FT-IR spectra of different kidney stone samples were recorded in the range of 4000-400 cm-1. By identifying the characteristic frequency, the chemical compositions of the samples are determined. The results analyzed by FTIR technique were confirmed by X-RD method, in which the recorded X-ray diffractogram are compared with JCPDS files using search match method. Further analysis of XRD pattern also reveals the same. [ABSTRACT FROM AUTHOR]
- Published
- 2008
- Full Text
- View/download PDF
41. Flexible spectrum management for mobile broadband services: How does it vary across advanced and emerging markets?
- Author
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Sridhar, Varadharajan, Casey, Thomas, and Hämmäinen, Heikki
- Subjects
- *
SPECTRUM analysis , *MOBILE communication systems , *EMERGING markets , *ECONOMIC demand , *INTERNET , *INDUSTRIAL organization (Economic theory) , *MATHEMATICAL models - Abstract
Abstract: Demand for wireless data and Internet services are expected to grow exponentially, both in advanced and emerging markets in the near future. While advanced countries have often used centralized planning and coordination methodology to forecast and allocate the associated spectrum blocks to wireless operators for meeting the demand, it is often ad-hoc in emerging markets dictated by market forces. In this paper, Finland and India are taken to represent advanced and emerging markets, respectively. Different policy options and the policy environment in these two countries for spectrum management are explored. A causal model is constructed to represent the different variables that affect spectrum management practices and possible paths forward in these two extreme cases are highlighted. Using the causal model structure, it is hypothesized that (i) the matured markets such as Finland that practice centralized and harmonized spectrum planning are likely to continue their ex-ante policies and opt for the release of digital dividend spectrum and use of spectrally efficient technologies; (ii) the emerging market in India that is characterized by a market oriented ex-poste regulation is a good candidate to introduce secondary markets including flexible opportunistic spectrum access as exemplified by the wide spread adoption of multi-SIM handsets and the practice of national roaming by 3G service providers. Introductions of policies and regulations in these markets to break away from the extant paths are also highlighted. [Copyright &y& Elsevier]
- Published
- 2013
- Full Text
- View/download PDF
42. A field technique for rapid lithological discrimination and ore mineral identification: Results from Mamandur Polymetal Deposit, India.
- Author
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RAMAKRISHNAN, D, NITHYA, M, SINGH, K, and BHARTI, RISHIKESH
- Subjects
- *
PETROLOGY , *MINERALS , *SEDIMENTATION & deposition , *PROSPECTING , *SPECTRUM analysis , *LINEAR statistical models , *X-ray diffraction , *STANDARD deviations - Abstract
This work illustrates the efficiency of field spectroscopy for rapid identification of minerals in ore body, alteration zone and host rocks. The adopted procedure involves collection of field spectra, their processing for noise, spectral matching and spectral un-mixing with selected library end-members. Average weighted spectral similarity and effective peak matching techniques were used to draw end-members from library. Constrained linear mixture modelling technique was used to convolve end-member spectra. Linear mixture model was optimized based on root mean square error between field- and modelled-spectra. Estimated minerals and their abundances were subsequently compared with conventional procedures such as petrography, X-ray diffraction and X-ray fluorescence for accuracy assessment. The mineralized zone is found to contain azurite, galena, chalcopyrite, bornite, molybdenite, marcacite, gahnite, hematite, goethite, anglesite and malachite. The alteration zone contains chlorite, kaolinite, actinolite and mica. These mineral assemblages correlate well with the petrographic measurements ( R = 0.89). Subsequently, the bulk chemistry of field samples was compared with spectroscopically derived cumulative weighted mineral chemistry and found to correlate well ( R = 0.91-0.98) at excellent statistical significance levels (90-99%). From this study, it is evident that field spectroscopy can be effectively used for rapid mineral identification and abundance estimation. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
43. ONE THIRD OCTAVE ANALYSIS: A DIAGNOSTIC TOOL TO MEASURE NASALITY IN CONJUNCTION WITH NASALANCE IN CHILDREN WITH REPAIRED CLEFT LIP AND PALATE.
- Author
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Navya, A. and Pushpavathi, M.
- Subjects
CLEFT lip ,CLEFT palate ,PROBABILITY theory ,SPECTRUM analysis ,SPEECH disorders in children ,RECEIVER operating characteristic curves ,DATA analysis software - Abstract
Hypernasality is the most predominant feature perceived in speech of individuals with cleft lip and palate. Instrumental assessment of speech can provide additional information along with the perceptual evaluation of speech for accuracy in diagnosis in individuals with cleft lip and palate (CLP). The widely used objective assessment of nasality is measuring nasalance using Nasometer. However, the spectral analysis of nasality in speech can provide complementary information along with nasalance measures. Hence, the present study is aimed to measure nasalance values and one third octave spectral peaks and their ability to differentiate children with repaired cleft lip and palate (RCLP) from control group. The study included eight children with RCLP age ranging from six to ten years. The control group included sixteen typically developing age and gender matched children. Vowel /a/ and /i/ was selected as stimuli. Nasalance was measured using Nasometer and 1/3
rd octave spectral analysis was measured using a specially designed MATLAB programme. Statistical analysis was performed using SPSS 17 software. To differentiate the groups with the cutoff values, sensitivity and specificity of the variables was derived using receiver operating curves (ROC). The results showed high sensitivity and specificity of the nasalance values with the cutoff of 8.8% for /a/ and 31.6% for /i/. The frequency region between 998Hz and 2663 Hz provided high sensitivity and specificity for differentiating groups using 1/3rd octave spectra analysis. Further studies are required to generalize the results of one third octave spectra analysis. [ABSTRACT FROM AUTHOR]- Published
- 2013
44. Simultaneous estimation of earthquake source parameters and crustal Q value from broadband data of selected aftershocks of the 2001 M 7.7 Bhuj earthquake.
- Author
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SAHA, A, LIJESH, S, and MANDAL, P
- Subjects
- *
EARTHQUAKE aftershocks , *PARAMETER estimation , *GUJARAT Earthquake, India, 2001 , *SPECTRUM analysis , *SEISMIC tomography , *SEISMOLOGY - Abstract
This paper presents the simultaneous estimation of source parameters and crustal Q values for small to moderate-size aftershocks ( M 2.1-5.1) of the $M_{w }$7.7 2001 Bhuj earthquake. The horizontal-component S-waves of 144 well located earthquakes (2001-2010) recorded at 3-10 broadband seismograph sites in the Kachchh Seismic Zone, Gujarat, India are analyzed, and their seismic corner frequencies, long-period spectral levels and crustal Q values are simultaneously estimated by inverting the horizontal component of the S-wave displacement spectrum using the Levenberg-Marquardt nonlinear inversion technique, wherein the inversion scheme is formulated based on the ω-square source spectral model. The static stress drops (Δ σ) are then calculated from the corner frequency and seismic moment. The estimated source parameters suggest that the seismic moment ( M) and source radius ( r) of aftershocks are varying from 1.12 × 10 to 4.00 × 10N-m and 132.57 to 513.20 m, respectively. Whereas, estimated stress drops (Δ σ) and multiplicative factor ( E) values range from 0.01 to 20.0 MPa and 1.05 to 3.39, respectively. The corner frequencies are found to be ranging from 2.36 to 8.76 Hz. The crustal S-wave quality factor varies from 256 to 1882 with an average of 840 for the Kachchh region, which agrees well with the crustal Q value of the seismically active New Madrid region, USA. Our estimated stress drop values are quite large compared to the other similar size Indian intraplate earthquakes, which can be attributed to the presence of crustal mafic intrusives and aqueous fluids in the lower crust as revealed by the earlier tomographic study of the region. [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
45. Analysis of the potential of kimberlite rock spectra as spectral end member using samples from Narayanpet Kimberlite Field, Andhra Pradesh.
- Author
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Guha, Arindam, Rao, D. Ananth, Ravi, S., Kumar, K. Vinod, and Rao, E. N. Dhananjaya
- Subjects
- *
KIMBERLITE , *SPECTRUM analysis , *ROCKS , *MINES & mineral resources , *REMOTE sensing , *MINERALOGY - Abstract
Mineral spectra as an end-member have been used for spatial mapping of the mineral deposits and associated potential lithovariants (altered rocks, etc.) while processing the remotely sensed hyperspectral data. But in nature, minerals occur in a mixture in rocks. Therefore, characterization of rock spectra is important. Here we study the role of texture, grain size and relative mineralogical abundances of constituent minerals in shaping the spectral features of the rock spectra in the visible-near infrared and shortwave infrared (VNIR-SWIR) domain. In this regard, analysis of kimberlite rock spectra is carried out to understand how absorption features of its constituent minerals are preserved in the spectral profiles of two different types of kimberlites with distinct mineral assemblages; one serpentine-rich and the other carbonate-rich. It has been observed that the spectral signature of the rock is controlled by the diagnostic absorption features of dominant constituent minerals. However, wavelength and depth of the diagnostic absorption feature of the dominant constituent mineral are modified in the rock spectra due to nonlinear spectral mixing with spectral features of other constituent minerals of the rock. It is observed that the spectral profiles of the rocks are not influenced by the fabric and grain size variation, except for the variation in the albedo or background reflectance of the spectral profiles. Spectral features of the rock also remain stable with the changes in the spectral measurement parameters. Therefore, it is concluded that the rock spectra can be used as an end-member or reference for spatial mapping of the economic rock instead of its constituent minerals. [ABSTRACT FROM AUTHOR]
- Published
- 2012
46. Distinct ruby suite at Sardapur, Orissa: A spectroscopic investigation.
- Author
-
Majumdar, Alik and Mathew, George
- Subjects
- *
RUBIES , *CORUNDUM , *ELECTRON paramagnetic resonance , *SPECTRUM analysis , *CHARGE transfer - Abstract
Orissa is an important area for gem variety of corundum deposits in India. Spectroscopic studies, such as ESR, OAS on samples from Sardapur, Orissa, were carried out to ascertain the colour cause of corundum. Electron spin resonance (ESR) spectroscopic study was carried out on the samples to detect the presence of paramagnetic ions i.e. Fe, Fe, Ti, Cr and V etc. The variable temperature experiment carried out to observe the effect of heating on peak valence state change in paramagnetic ions. Samples were cut and polished to obtain the optical absorption spectrum (OAS) to detect the colour causing transition ions/defect centres. The samples of gem variety were step heated up to 300°C for colour enhancement studies. EPMA analysis has revealed the low chromium concentration in the rubies. The varying hues of red in the corundum are due to the presence of bivalent and trivalent iron and charge transfer process along with Cr absorption in the 550 nm region. [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
47. An overview of the causes of current practices in Pratinidhi Dravyas (substitution of drugs) in Ayurveda including newer techniques for their evaluation.
- Author
-
Joshi, Pravin R., Patel, Bhupesh R., and Shukla, Vinay J.
- Subjects
AYURVEDIC medicine ,FOURIER transform infrared spectroscopy ,PHARMACEUTICAL research ,MEDICAL practice ,SPECTRUM analysis - Abstract
Many Pratinidhi Dravyas in Ayurvedic classics are mentioned and certainly are based on a methodical approach, which involves many aspects. These principles on which Pratinidhis were decided are quoted nowhere; so both to understand the established Pratinidhis and to find new ones a rational approach is the need of the hour. This article is an effort in the direction to study this concept meticulously in light of modern techniques for its better understanding and application. As there are very few established parameters, which help for selection and evaluation of Pratinidhi Dravyas. A rational technique like Fourier transform infrared spectroscopy may be incorporated to set a new dimension. As most of the routine analytical techniques are separation based, overall component load cannot be predicted. Thus, it is prime necessity to compare the drugs with a whole aspect, which goes in hand by hand with a holistic approach of Ayurveda "Treat the man as Whole -- Take the drug as whole." [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
48. Utilization of Hyperion data over Dongargarh, India, for mapping altered/weathered and clay minerals along with field spectral measurements.
- Author
-
Bhattacharya, S., Majumdar, T. J., Rajawat, A. S., Panigrahi, M. K., and Das, P. R.
- Subjects
- *
SPECTRUM analysis , *CLAY minerals , *GEOLOGICAL mapping - Abstract
Hyperion data acquired over Dongargarh area, Chattisgarh (India), in December 2006 have been analysed to identify dominant mineral types present in the area, with special emphasis on mapping the altered/weathered and clay minerals present in the rocks and soils. Various advanced spectral processes such as reflectance calibration of the Hyperion data, minimum noise fraction transformation, spectral feature fitting (SFF) and spectral angle mapper (SAM) have been used for comparison/mapping in conjunction with spectra of rocks and soils that have been collected in the field using Analytical Spectral Devices's FieldSpec instrument. In this study, 40 shortwave infrared channels ranging from 2.0 to 2.4 μm were analysed mainly to identify and map the major altered/weathered and clay minerals by studying the absorption bands around the 2.2 and 2.3 μm wavelength regions. The absorption characteristics were the results of O–H stretching in the lattices of various hydrous minerals, in particular, clay minerals, constituting altered/weathered rocks and soils. SAM and SFF techniques implemented in Spectral Analyst were applied to identify the minerals present in the scene. A score of 0–1 was generated for both SAM and SFF, where a value of 1 indicated a perfect match showing the exact mineral type. Endmember spectra were matched with those of the minerals as available in the United States Geological Survey Spectral Library. Four minerals, oligoclase, rectorite, kaolinite and desert varnish, have been identified in the studied area. The SAM classifier was then applied to produce a mineral map over a subset of the Hyperion scene. The dominant lithology of the area included Dongargarh granite, Bijli rhyolite and Pitepani volcanics of Palaeo-Proterozoic age. Feldspar is one of the most dominant mineral constituents of all the above-mentioned rocks, which is highly susceptible to chemical weathering and produces various types of clay minerals. Oligoclase (a feldspar) was found in these areas where mostly rock outcrops were encountered. Kaolinite was also found mainly near exposed rocks, as it was formed due to the weathering of feldspar. Rectorite is the other clay mineral type that is observed mostly in the southern part of the studied area, where Bijli rhyolite dominates the lithology. However, the most predominant mineral type coating observed in this study is desert varnish, which is nothing but an assemblage of very fine clay minerals and forms a thin veneer on rock/soil surfaces, rendering a dark appearance to the latter. Thus, from this study, it could be inferred that Hyperion data can be well utilized to identify and map altered/weathered and clay minerals based on the study of the shape, size and position of spectral absorption features, which were otherwise absent in the signatures of the broadband sensors. [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
49. Spatiotemporal dimensionality and Time-Space characterization of multitemporal imagery
- Author
-
Small, Christopher
- Subjects
- *
SPATIOTEMPORAL processes , *TIME series analysis , *SPECTRUM analysis , *PRINCIPAL components analysis , *PHENOLOGY , *LANDSAT satellites , *MODIS (Spectroradiometer) - Abstract
Abstract: Spatiotemporal dimensionality refers to the continuum of spatial and temporal patterns in an image time series. Time-Space characterization refers to a way of representing this continuum of patterns as combinations of spatial and temporal constituents — with a minimum of assumptions about the forms of the patterns. Patterns can be related to processes through modeling. By combining characterization and modeling, two complementary analytical tools can be used together so that each resolves a key limitation of the other. This study describes a straightforward extension of Principal Component Analysis and Spectral Mixture Analysis to multitemporal imagery and illustrates how characterization of the dimensionality and eigenstructure of the data can inform modeling of the processes represented in the data. The relationships among spatiotemporal processes can be represented as combinations of temporal endmembers in a temporal feature space where the dimensions represent different components of the temporal patterns present in the data. The topology of the feature space and the processes being modeled together inform the selection of temporal endmembers and the structure of the model chosen to represent the processes. The dimensionality revealed by the characterization can also provide a partial solution to the problem of endmember variability. The characterization and modeling process is illustrated with the vegetation phenology of the Ganges–Brahmaputra delta using a MODIS vegetation index time series. Additional applications and limitations of Time-Space characterization and mixture modeling are further illustrated by comparing the eigenstructures and temporal feature spaces of Landsat vegetation fraction and DMSP-OLS night light time series. [Copyright &y& Elsevier]
- Published
- 2012
- Full Text
- View/download PDF
50. Co-existence of wind seas and swells along the west coast of India during non-monsoon season.
- Author
-
Rashmi, R., Aboobacker, V. M., Vethamony, P., and John, M. P.
- Subjects
ACQUISITION of data ,SPECTRUM analysis ,OCEAN waves ,WIND waves ,MONSOONS ,COASTS - Abstract
Wave data collected along the west coast of India (off Goa, Ratnagiri and Dwarka) during non-monsoon season have been analysed to study the co-existence of wind seas and swells. Diurnal variation in wind and wave parameters is noticeable along the central west coast of India (off Goa and Ratnagiri), and this is not present along the northwest coast of India (off Dwarka). Swells are predominantly mature (91 %) and old (88 %) during late pre-monsoon and post-monsoon seasons, respectively. Sea Swell Energy Ratio quantifies wind sea, swell and mixed seas prevailing in the regions during non-monsoon season. Intermodal Distance (ID) between the energy peaks is moder ately separated during non-monsoon season, whereas, during the shamal events, energy peaks are very close to each other (ID~ 0). However, pure wind seas (ID~ 1) are found to co-exist with the swells during non-monsoon season. Wind seas are growing, when wind and wind seas are opposite to swell direction. Wind seas have minimum angular spreads in multimodal state. Under low winds, the interaction between wind sea and swell dominates and thereby the multimodal state reduces to unimodal state. The fetch available for the evolution of the wind sea spectrum has been estimated, and it is found to be less than 150 km. For the fetch limited condition, a non-dimensional empirical relation has been derived relating the significant wind sea height in terms of wind speed and peak wind sea period, and this relation fits for the west coast of India. [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
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