363 results on '"Santanu Banerjee"'
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2. Paleoenvironmental implications of interbasaltic volcaniclastic sediments within Late Cretaceous Deccan volcanics, India
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Pragya Singh, Santanu Banerjee, and Kanchan Pande
- Abstract
The Deccan volcanic province is extensively studied for the occurrence of the K–Pg boundary, Cretaceous mass extinction, associated climate change and biotic crises. The Late Cretaceous volcaniclastic sediments occurring in between the lava flow, known as bole beds, are often overlooked. These bole beds, however, are useful to understand the paleoenvironmental conditions during non-eruptive phases of Deccan volcanism. A comprehensive study involving field, petrography and mineralogical investigations focuses on a few cm to a few m-thick bole beds of variable lateral continuity.Field observations of bole beds reveal red to green colour and variable geometry i.e., massive, bedded, lensoid etc. Petrographic study reveals differences in textural and mineralogical characteristics of red and green boles. Red boles show an incipient to moderate degree of pedogenesis. The incipiently pedogenised red boles show the dominance of volcanic lithic fragments (lathwork, microlitic and vitric), scoria, plagioclase, and pyroxene. The moderately pedogenised red boles, show dominance of altered basaltic clasts (100 μm to 5 mm), iron glaebules, alteromorph and oxidized fragments set in the fine-grained clayey groundmass. The green bole, however, shows poor pedogenesis, with predominance of volcaniclastic fragments, plagioclase, pyroxene and opaques. The volcanic glasses and minerals in green boles are thoroughly replaced by green clay. X-ray diffraction study shows presence of hematite and 14 Å smectite in red bole. The green bole, however, contains 10 Å celadonite and 14 Å smectite as major clay minerals. FTIR and VNIR spectroscopy further confirm the slight difference in composition of smectite associated with bole beds, i.e., Fe, Al-rich smectite in red boles and Fe, Mg-rich smectite in green boles. Although the original material for forming red and green boles is basalt-derived, the distribution pattern of green boles is not as extensive as red boles. This indicates difference in the paleoenvironment of formation of the two bole beds. The study of red bole suggests its formation in oxic, subaerial conditions. The relatively thick red bole units (up to a few m), showing gradational contact with lower basalt and distinct pedogenic features, mark prominent breaks in Deccan eruptions. However, the cm-scaled red bole units, showing uneven boundary with lower basalt, and containing abundant volcaniclastic fragments, indicate minor breaks in volcanism. Green boles, on the contrary, indicate confined suboxic conditions in local depressions on the Deccan lava flow.
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- 2023
3. Glauconitization within the late Cretaceous Mahadek Formation and its stratigraphic implications
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Dipima Borgohain, Sarat Phukan, and Santanu Banerjee
- Abstract
This study explores sedimentological and stratigraphical implications of glauconites within the upper Cretaceous Mahadek Formation exposed at the Umsohryngkew River section in Meghalaya, India. The succession is overall fining upward, with sandstone dominating the lower part and calcareous shales and limestone bands constituting the upper part of the Mahadek Formation. Glauconite occurs within the impure limestone and shale beds of the upper part of the sequence. The glauconitic section gradationally passes upward to K/Pg boundary above the Mahadek Formation. Textural, mineralogical and chemical analyses were carried out to understand the origin of the glauconite. Petrographic investigation reveals three main types of glauconites, a) pellet b) vermiform c) infilling within bioclasts. The glauconite appears dark green and the long dimension of the glauconite grain averages 200 µm. Occasionally, the glauconite grains may be as long as 500 µm. The glauconite pellets show sharp boundaries and exhibit internal cracks. The content of glauconite grain is nearly 15-20 % of the rock volume. These are sub-rounded to rounded in shape without showing evidence of transportation. X-Ray Diffraction on air-dried samples reveals very prominent (001) basal reflection at 10.23 Å, with reflections of (020), , , (003) and (060) planes at 4.52 Å, 4.23 Å, 3.66 Å, 3.27 Å, 5.51 Å respectively. On glycolation, the (001) peak shifts from 10.23 Å to 9.95 Å, while and (003) reflections collapse into one single peak. The peaks get narrower, more symmetrical and sharper after heating the samples at 400oC. Also, the and (003) reflections show separations into 3.33 Å and 3.30 Å reflections respectively. The X-Ray diffraction characteristics confirm the pure nature of glauconite devoid of any interstratification. FEG-SEM imaging of glauconite grains shows a perfect lamellar structure and corroborates the X-Ray diffraction patterns of glauconites. Further, the electron microprobe analyses data show average K2O content of the glauconite is 6.5 %, suggesting an evolved variety. The Fe2O3(total) content varies from 2.9 % to 16.8 %, with an average of 9.9 %. While the average content of Al2O3 is 20.3%. The K2O vs Fe2O3 plot (r2= 0.7) shows a strong positive correlation. The inverse correlation (r2 = 0.8) between Fe2O3 and Al2O3 suggests the replacement of Al by Fe at octahedral sites. The averages of MgO, SiO2 are 3.5% and 52.6% respectively. The evolved glauconite within the shelfal Mahadek Formation demarcates the stratigraphic condensation at the top of the transgressive deposits. The formation of glauconite in the late Cretaceous Mahadek Formation is significant because of its stratigraphic preference close to the K/Pg boundary.
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- 2023
4. Tracking sources and paleotectonic settings of Mesozoic sandstones in interlinked rift basins of western India: An integrated approach using petrography and heavy mineral chemistry
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Pawan Kumar Rajak, Angana Chaudhuri, Naraga Prabhakar, and Santanu Banerjee
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Geography, Planning and Development ,Paleontology ,Earth-Surface Processes - Published
- 2022
5. Chronic wound microenvironment mediates selection of biofilm-forming multi drug resistant Staphylococcus epidermidis with capability to impair healing
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Irena Pastar, Miroslav Dinic, Rebecca Verpile, Jingjing Meng, Jelena Marjanovic, Jamie Burgess, Lisa Plano, Suzanne Hower, Seth Thaller, Santanu Banerjee, Hadar Lev-Tov, and Marjana Tomic-Canic
- Abstract
Venous leg ulcers (VLU) are the most common chronic wounds characterized by bacterial biofilms and perturbed microbiome. Staphylococcus epidermidis is primarily known as skin commensal beneficial for the host, however, some strains can form biofilms and cause infections. By employing shotgun metagenomic sequencing we show that genetic signatures of antimicrobial resistance, adhesion and biofilm formation in VLU isolates correlate with in vitro bacterial traits. We demonstrate that the capability of chronic wound isolates to form biofilms and elicit IL-8 and IL-1β expression in human ex vivo wounds, correlates with the non-healing outcomes in patients with VLU. In contrast, commensal strains were incapable of surviving in the human ex vivo wounds. We show that major fitness traits of S. epidermis from VLU involve genes for resistance to methicillin and mupirocin, while the biofilm formation relied on the minimal number of genetic elements responsible for bacterial binding to fibronectin and fibrinogen. This underscores the importance of the emergence of treatment resistant virulent lineages in patients with non-healing wounds.
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- 2023
6. FAPbI3 Perovskite Films Prepared by Solvent Self-Volatilization for Photovoltaic Applications
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Qiqi Zhang, Guorong Ma, Kevin A. Green, Kristine Gollinger, Jaiden Moore, Teresa Demeritte, Paresh Chandra Ray, Glake Alton Hill, Xiaodan Gu, Sarah E. Morgan, Manliang Feng, Santanu Banerjee, and Qilin Dai
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Materials Chemistry ,Electrochemistry ,Energy Engineering and Power Technology ,Chemical Engineering (miscellaneous) ,Electrical and Electronic Engineering - Published
- 2022
7. An Assessment of Alternate Fertilizer Potential of Glauconite Deposits in India using Simple Beneficiation Methods
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Tathagata Roy Choudhury, P. V. Sunder Raju, Tehreen Shaikh, and Santanu Banerjee
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Geology - Published
- 2022
8. Larger Benthic Foraminifera and Microfacies of Late Paleocene - Early Eocene Sections in Meghalaya, Northeast India
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Christer Dominique Pereira, Sonal Khanolkar, Santanu Banerjee, Ercan Özcan, and Pratul Kumar Saraswati
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Paleontology ,Microbiology - Abstract
The Late Paleocene-Early Eocene sections from Lakadong Limestone (Mawmluh Quarry) and Umlatdoh Limestone (Komorrah Quarry) in Meghalaya, Northeast India were examined for larger benthic foraminiferal microfacies and carbon isotopes. We generated high-resolution age models using larger benthic foraminifera biostratigraphy and recorded the change in microfacies. The LBF microfacies in SBZ 3 (∼58–60.7 Ma) and SBZ 4 (56–58Ma) is dominated by Miscellanea, Glomalveolina, Ranikothalia, orthophragminids, dasycladalean green algae and coralline red algae, indicating that deposition occurred within inner to mid-ramp environments. An abrupt shift in the depositional setting from open marine Lakadong Limestone to restricted marine Lakadong Sandstone across the PETM possibly indicates major changes in hydrological cycle during the extreme warmth that followed the PETM. The marine sedimentation continued during the Early Eocene (SBZ 7–9 corresponding to 55.1–52.8 Ma) within Meghalaya that led to the formation of Umlatdoh Limestone dominated by Halimeda, Alveolina, and miliolids. The larger foraminiferal extinction and origination in the Meghalaya basin is marked by the extinction of late Palaeocene Ranikothalids, Glomalveolinids, dominating the Lakadong Limestone and the dominance of Alveolinids and Discocylinids in the early Eocene Umlatdoh Limestone.
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- 2022
9. Fecal Microbial Transplant in Individuals With Immune-Mediated Dry Eye
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Harrison Dermer, Anat Galor, Santanu Banerjee, Mario Rojas, Kara M. Cavuoto, Joanne O Day, and Arjun Watane
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Male ,medicine.medical_specialty ,medicine.medical_treatment ,Population ,Gastroenterology ,Article ,Feces ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,medicine ,Prevotella ,Humans ,Microbiome ,Alistipes ,Adverse effect ,education ,030304 developmental biology ,0303 health sciences ,education.field_of_study ,biology ,business.industry ,Microbiota ,Enema ,Fecal Microbiota Transplantation ,Middle Aged ,biology.organism_classification ,Gastrointestinal Microbiome ,Ophthalmology ,Treatment Outcome ,030221 ophthalmology & optometry ,Population study ,Dry Eye Syndromes ,business - Abstract
Purpose: To evaluate the safety of the Fecal Microbial Transplant for Sjogren Syndrome (FMT) trial in individuals with immune-mediated dry eye (DE). Design: Open-label, nonrandomized clinical trial. Methods: The study population included 10 individuals with DE symptoms and signs meeting criteria for Sjogren or positive early Sjogren markers. Procedures were 2 FMTs from a single healthy donor delivered via enema, 1 week apart. The primary outcome measure was safety. In addition, gut microbiome profiles, DE metrics, and T-cell profiles in blood were examined at baseline before FMT, and at 1 week, 1 month, and 3 months after FMT. Results: The mean age of the population was 60.4 years; 30% were male; 50% were white; and 50% were Hispanic. At baseline, all subjects had significantly different gut microbiome profiles from the donor, including higher mean diversity indices. Subjects had a decreased abundance of genera Faecalibacterium, Prevotella, and Ruminococcus and an increased abundance of genera Alistipes, Streptococcus, and Blautia compared to the donor. Effector and regulatory T-cell profiles were positively correlated with each other and with DE symptom severity (T helper 1 cells [Th1]; r = .76; P = .01; Th17: r = 0.83; P = .003; CD25: r = 0.66; P = .04; FoxP3: r = 0.68; P = .03). No adverse events were noted with FMT. After FMT, gut microbiome profiles in 8 subjects moved closer to the donor's profile. As a group, gut microbiome profiles at all follow-up time points were more similar to the original recipients’ than the donor's microbiome; however, certain phyla, classes, and genera operational taxonomic unit (OTU) numbers remained closer to the donor vs recipients’ baseline profiles out to 3 months. Five individuals subjectively reported improved dry eye symptoms 3 months after FMT. Conclusions: FMT was safely performed in individuals with immune-mediated DE, with certain bacterial profiles resembling the donor out to 3 months after FMT. One-half the subjects reported improved DE symptoms. The most effective FMT administration method has yet to be determined.
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- 2022
10. Lower respiratory tract microbiome composition and community interactions in smokers
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Michael Campos, Trevor Cickovski, Mitch Fernandez, Melita Jaric, Adam Wanner, Gregory Holt, Elio Donna, Eliana Mendes, Eugenia Silva-Herzog, Lisa Schneper, Jonathan Segal, David Moraga Amador, Juan Daniel Riveros, Vanessa Aguiar-Pulido, Santanu Banerjee, Matthias Salathe, Kalai Mathee, and Giri Narasimhan
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General Materials Science - Abstract
The lung microbiome impacts on lung function, making any smoking-induced changes in the lung microbiome potentially significant. The complex co-occurrence and co-avoidance patterns between the bacterial taxa in the lower respiratory tract (LRT) microbiome were explored for a cohort of active (AS), former (FS) and never (NS) smokers. Bronchoalveolar lavages (BALs) were collected from 55 volunteer subjects (9 NS, 24 FS and 22 AS). The LRT microbiome composition was assessed using 16S rRNA amplicon sequencing. Identification of differentially abundant taxa and co-occurrence patterns, discriminant analysis and biomarker inferences were performed. The data show that smoking results in a loss in the diversity of the LRT microbiome, change in the co-occurrence patterns and a weakening of the tight community structure present in healthy microbiomes. The increased abundance of the genus Ralstonia in the lung microbiomes of both former and active smokers is significant. Partial least square discriminant and DESeq2 analyses suggested a compositional difference between the cohorts in the LRT microbiome. The groups were sufficiently distinct from each other to suggest that cessation of smoking may not be sufficient for the lung microbiota to return to a similar composition to that of NS. The linear discriminant analysis effect size (LEfSe) analyses identified several bacterial taxa as potential biomarkers of smoking status. Network-based clustering analysis highlighted different co-occurring and co-avoiding microbial taxa in the three groups. The analysis found a cluster of bacterial taxa that co-occur in smokers and non-smokers alike. The clusters exhibited tighter and more significant associations in NS compared to FS and AS. Higher degree of rivalry between clusters was observed in the AS. The groups were sufficiently distinct from each other to suggest that cessation of smoking may not be sufficient for the lung microbiota to return to a similar composition to that of NS.
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- 2022
11. Feasibility study of a high spatial and time resolution beam emission spectroscopy diagnostic for localized density fluctuation measurements in Lithium Tokamak eXperiment-β (LTX-β)
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Santanu Banerjee, D. P. Boyle, A. Maan, R. Majeski, R. Kaita, D. Smith, M. von Hellermann, C. Hansen, W. Capecchi, and D. Elliott
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Instrumentation - Abstract
Trapped electron mode (TEM) is the main source of turbulence predicted for the unique operation regime of a flat temperature profile under low-recycling conditions in the LTX-β tokamak, while ion temperature gradient driven turbulence may also occur with gas fueling from the edge. To investigate mainly TEM scale density fluctuations, a high spatial and time resolution 2D beam emission spectroscopy (BES) diagnostic is being developed. Apart from spatially localized density turbulence measurement, BES can provide turbulence flow and flow shear dynamics. This BES system will be realized using an avalanche photodiode-based camera and narrow band interference filter. The system can acquire data at 2 MHz. Simulations with the Simulation of Spectra (SOS) code indicate that a high signal to noise ratio can be achieved with the proposed system. This will enable sampling the density fluctuations at this high time resolution. The design considerations and system optimization using the SOS code are presented.
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- 2022
12. Obesity enriches for tumor protective microbial metabolites and treatment refractory cells to confer therapy resistance in PDAC
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Kousik, Kesh, Roberto, Mendez, Beatriz, Mateo-Victoriano, Vanessa T, Garrido, Brittany, Durden, Vineet K, Gupta, Alfredo, Oliveras Reyes, Nipun, Merchant, Jashodeep, Datta, Santanu, Banerjee, and Sulagna, Banerjee
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Mice, Inbred C57BL ,Pancreatic Neoplasms ,Microbiology (medical) ,Mice ,Infectious Diseases ,Nucleoside Q ,Gastroenterology ,Animals ,Obesity ,Diet, High-Fat ,Microbiology ,Gastrointestinal Microbiome - Abstract
Obesity causes chronic inflammation and changes in gut microbiome. However, how this contributes to poor survival and therapy resistance in patients with pancreatic cancer remain undetermined. Our current study shows that high fat diet-fed obese pancreatic tumor bearing mice do not respond to standard of care therapy with gemcitabine and paclitaxel when compared to corresponding control diet-fed mice. C57BL6 mice were put on control and high fat diet for 1 month following with pancreatic tumors were implanted in both groups. Microbiome of lean (control) and obese (high fat diet fed) mice was analyzed. Fecal matter transplant from control mice to obese mice sensitized tumors to chemotherapy and demonstrated extensive cell death. Analysis of gut microbiome showed an enrichment of queuosine (Q) producing bacteria in obese mice and an enrichment of S-adenosyl methionine (SAM) producing bacteria in control diet-fed mice. Further, supplementation of obese animals with SAM sensitized pancreatic tumors to chemotherapy. Treatment of pancreatic cancer cells with Q increased PRDX1 involved in oxidative stress protection. In parallel, tumors in obese mice showed increase in CD133
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- 2022
13. Authigenic Fe Mineralization in Shallow to Marginal Marine Environments: A Case Study from the Late Paleocene—Early Eocene Cambay Shale Formation
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Tathagata Roy Choudhury, Pragya Singh, Arpita Chakraborty, and Santanu Banerjee
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Geology ,Geotechnical Engineering and Engineering Geology ,glauconite ,chamosite ,siderite ,early Eocene ,warm climate ,Cambay Basin - Abstract
The late Paleocene–early Eocene warm greenhouse conditions, characterized by elevated pCO2 levels in the atmosphere and a dramatic increase in sea surface temperature, prompted abundant authigenic glauconite formation within the shallow marine sediments worldwide by lowering the net sedimentation rate, increasing organic productivity and expanding the oxygen minimum zones to shallow oceans. The early Eocene marginal marine Cambay Shale Formation experienced episodes of marine inundation represented by limestone–green shale alternations. The shales host abundant authigenic light-green, dark-green, and brown pellets. A detailed characterization of the pellets of the Valia and Vastan lignite mines, integrating the sedimentological, petrographical, mineralogical, and mineral geochemical data, suggests two distinct varieties of Fe–silicate formation, viz. glauconite and chamosite. While the glauconitic green pellets are ubiquitous to Valia and Vastan mines, brown chamosite pellets are confined within the basal part of the green shale facies alternating with fossiliferous limestone in the Vastan mine. The glauconites of the Valia mine manifest a ‘nascent’ to ‘slightly evolved’ maturation stage of glauconitization, whereas the glauconites of the Vastan mine represent the ‘evolved’ type. The limestone–green shale alternation in the Valia mine is overlain by a ~4 m-thick spherulitic mudstone facies comprising monomineralic sideritic spherulites, reflecting a pure FeCO3 composition. The glauconites in the Cambay Shale Formation transformed from kaolinite-rich clay pellets under dys-oxic depositional conditions. The increasing anoxicity within the microenvironment, possibly amplified by the rapid oxidation of continent-derived organic matter, facilitated chamosite formation instead of glauconite. The increased freshwater influx into the marginal marine depositional environment resulted in immature, K-poor glauconites of the Valia mine. The formation of siderite spherulites overlying the limestone–green shale alternation relates to the beginning of the regressive phase of sedimentation.
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- 2023
14. Reply to Comment on 'Larger Benthic Foraminifera and Microfacies of Late Paleocene - Early Eocene Sections in Meghalaya, Northeast India' by Hadi, M. (2022)
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Christer Dominique Pereira, Sonal Khanolkar, Santanu Banerjee, Ercan Özcan, and Pratul Kumar Saraswati
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Paleontology ,Microbiology - Published
- 2022
15. Petrographical and Geochemical Study of Syn-Rift Sediments, Pranhita-Godavari Intracratonic Gondwana Basin, India: Genesis and Paleo-Environmental Implications
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Sanghita Dasgupta, Santanu Banerjee, and Parthasarathi Ghosh
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General Earth and Planetary Sciences ,major element chemistry ,Middle Triassic to Early Jurassic ,Pranhita-Godavari syn-Rift Gondwana basin ,petrography ,provenance - Abstract
The approximately 2 km thick fluvio-lacustrine deposits of Pranhita-Godavari Gondwana syn-rift basin, ranging in age from 235 to 196 Ma, track the compositional changes from the Middle Triassic to Early Jurassic. Mineralogical and geochemical investigations, as well as paleocurrent data of the siliciclastic deposits of the four conformable formations—Yerrapalli, Bhimaram, Maleri and Dharmaram—trace the source of sediments to the south and southwest of the Gondwana basin. The dominance of arkosic to sub-arkosic sandstones in all the formations suggests mostly felsic sources. The high value of Zr/Sc, as well a high content of Hf, reflects the addition of zircon by sediment recycling. The index of compositional variability (ICV) and chemical index of alteration (CIA) values of these Gondwana samples suggest intermediate weathering of Proterozoic shales, granites and gneisses. The concentration of Cr and Ni, ratios of Eu/Eu* and (GdN/YbN) suggest a dominant post-Archean source. The insignificant variation in ICV and CIA values across the studied Mesozoic formations corroborates the continuation of syn-rift tectonics of the Pranhita-Godavari Gondwana basin since the Late Paleozoic. Sandstone samples show a gradual shift from arkose to subarkose in Yerrapalli, Barakar and Maleri formations, and to sublithic arenite sandstones in the younger Dharmaram formation, indicating recycling. However, the insignificant variation of feldspar and/or quartz content throughout these Mesozoic formations suggests lesser tectonic activity. The paleocurrent direction, shifting from NNW to NE direction, suggests a change in basin tectonism and/or sediment supply, which is corroborated by mineralogical and geochemical data.
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- 2022
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16. The Gut Microbiome and Sjögren’s
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Anat Galor, Kara M. Cavuoto, and Santanu Banerjee
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There has been a recent interest in the interaction between gut bacteria and mucosal immunity in a number of diseases, including Sjögren’s. Ample evidence is available showing that the gut microbiome is altered in individuals with autoimmune diseases such as Sjögren’s. Animal models have clarified that these are not just associations but that the gut microbiome affects disease phenotype. There are several methods by which to change the gut microbiome, and this may represent a potential treatment in Sjögren’s. More research is needed to identify the specific microbiome signature in Sjögren’s that can be used to guide preventive and therapeutic strategies.
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- 2022
17. Diagnostic Accuracy of Human Immunodeficiency Virus In Vitro Assays Evaluated by the World Health Organization Prequalification Evaluation Laboratories: Systematic Review and Meta-Analysis
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Santanu Banerjee, Mihir Bhatta, Srijita Nandi, Shanta Dutta, and Malay Kumar Saha
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Microbiology (medical) ,Infectious Diseases ,ROC Curve ,HIV ,Humans ,HIV Infections ,General Medicine ,Laboratories ,World Health Organization ,Sensitivity and Specificity - Abstract
To maintain the performance quality, human immunodeficiency virus (HIV) in vitro diagnostic (IVD) kits are required to be evaluated by unbiased health regulatory organizations following predefined guidelines. The World Health Organization (WHO) prequalification is one such program for the evaluation of IVD assays. In the present systematic review and meta-analysis, we analyzed and compared the 17 WHO prequalified public reports of HIV IVDs to yield summarized information for performance parameters. Pooled sensitivity, pooled specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio were used as overall performance evaluation parameters. High (≥98%) and comparable levels of sensitivity and specificity were observed for most of the assays. In addition, the overall diagnostic efficiency was observed to attain high precision, as evident by the value of the area under the curve (AUC) for the hierarchical summary receiver operating characteristic curve (AUC ≥ 0.98).
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- 2022
18. A Study on Urinary Glycated Albumin to urinary albumin excretion in gestational diabetes mellitus
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Satinath Mukhopadhyay, Santanu Banerjee, Kalyan Goswami, and Chandramallika Paul
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Pregnancy ,education.field_of_study ,medicine.medical_specialty ,Obstetrics ,business.industry ,Urinary system ,Public health ,advanced glycation end products ,Population ,lcsh:R ,lcsh:Medicine ,medicine.disease ,gestational diabetes mellitus ,Gestational diabetes ,Excretion ,Glycated albumin ,medicine ,glycated albumin ,Observational study ,General Agricultural and Biological Sciences ,education ,business - Abstract
Background: Gestational Diabetes Mellitus (GDM) is a public health problem in India with implications well pronounced in pregnancy and beyond. Biomarkers like Glycated Albumin (G.A.) can well monitor the glycaemic status and evaluate the transient hyperglycaemic spikes, which account for the diabetic complications. Aims and Objectives: In this study, we intend to study urinary G.A. excretion with respect to urinary albumin excretion expressed as UGA% in gestational diabetes mellitus. Materials and Methods: A prospective observational study was conducted for a period of 16 months on 177 pregnant women who attended antenatal clinics for the first time at a single centre.Among the surveyed population, 26 pregnant women subsequently developed GDM, and 31 healthy pregnant women who did not develop GDM were included in the study. Results: The UGA% between GDM and healthy mothers showed an increase in GDM with a p value
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- 2021
19. Late Paleocene-Early Eocene Foraminiferal Assemblage and Carbon Isotope Excursion Indicating Hyperthermal Events in Paleotropical Succession of Northwestern India
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Tathagata Roy Choudhury, Sonal Khanolkar, Santanu Banerjee, and Pratul Kumar Saraswati
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010506 paleontology ,Paleontology ,Carbon isotope excursion ,Assemblage (archaeology) ,Ecological succession ,010502 geochemistry & geophysics ,01 natural sciences ,Microbiology ,Geology ,0105 earth and related environmental sciences - Abstract
This study focuses on marine sediments of the late Paleocene-early Eocene (∼55.5–49 Ma) interval from the Jaisalmer Basin of western India. It demarcates the Paleocene Eocene Thermal Maximum (PETM) using foraminiferal biostratigraphy and carbon isotope stratigraphy. A negative carbon isotope excursion of 4.5‰ delineates the PETM within the basin. We demarcate five foraminiferal biofacies using the detrended correspondence analysis. These reflect characteristics of ecology, bathymetry, relative age, and environment of deposition of the foraminifera. They record the response of foraminifera to the warmth of the PETM. Biofacies A was deposited within an inner neritic setting ∼55.5 Ma and includes benthic foraminifera Haplophragmoides spp., Ammobaculites spp., and Lenticulina spp. The presence of Pulsiphonina prima and Valvulineria scorbiculata in Biofacies B suggests an increase in runoff conditions in the basin. Fluctuating trophic conditions prevailed between ∼54–50 Ma. It is evidenced by alternating Biofacies C (endobenthic and chiloguembelinids of eutrophic conditions) and Biofacies D (epibenthic and acarininids of oligotrophic conditions). Biofacies E is dominated by deep-dwelling parasubbotinids, indicating an increase in bathymetry, possibly corresponding to the Early Eocene Climatic Optimum (∼49 Ma).
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- 2021
20. The Application of Glauconite for High-Resolution Stratigraphic Interpretations of Eocene Succession
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Santanu Banerjee, Snehasis Chakrabarty, and Tathagata Roy Choudhury
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- 2022
21. The Geochemical Affinity of Paleogene Glauconites in Paleo-Tethyan Deposits of India
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Tathagata Roy Choudhury, Santanu Banerjee, and Sonal Khanolkar
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- 2022
22. Palaeoenvironmental implication of red and green palaeosol developed within lava flow of Deccan volcanic province, India
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Pragya Singh, Santanu Banerjee, and Kanchan Pande
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- 2022
23. An Analytical Solution of a Time-fractional Diffusion Equation Withexternal Force and Absorbent Term by Generalized Two-dimensional differential Transform Method
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Santanu Banerjee and Sudeshna Banerjee
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Differential transform method ,0209 industrial biotechnology ,020901 industrial engineering & automation ,Control and Systems Engineering ,020208 electrical & electronic engineering ,Mathematical analysis ,0202 electrical engineering, electronic engineering, information engineering ,Fractional diffusion ,02 engineering and technology ,Computer Science Applications ,Mathematics ,Term (time) - Abstract
In this paper, we have used generalized differential transform method in obtaining a general recurrencerelation for determining the solutions of time fractional diffusion equation with external force and absorbent term.Diffusion equations play an improtant part in energy transfer problems. Inclusion of fractional derivatives bring thenon-locality aspect into the physical system containing this equation. The obtained relation will help us to solvesuch equations with various external forces and initial conditions. Three illustrative examples have been discussed.
- Published
- 2020
24. The use of heavy mineral chemistry in reconstructing provenance: A case study from Mesozoic sandstones of Kutch Basin, India
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Angana Chaudhuri, N. Prabhakar, Arpita Das, and Santanu Banerjee
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Provenance ,Tourmaline ,Rutile ,Heavy mineral ,Geochemistry ,Geology ,Mesozoic ,Structural basin ,Mineral chemistry - Published
- 2020
25. Tracing multiple sources of sediments using trace element and Nd isotope geochemistry: provenance of the Mesozoic succession in the Kutch Basin, western India
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Santanu Banerjee, Angana Chaudhuri, Anirban Chatterjee, and Jyotiranjan S. Ray
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Provenance ,Igneous rock ,Precambrian ,Felsic ,Source rock ,Proterozoic ,Isotope geochemistry ,Geochemistry ,Geology ,Sedimentary rock - Abstract
An integrated approach involving Sr–Nd isotope, trace and rare earth element analyses tracks multiple sources of the Mesozoic sediments of the Kutch Basin at the western continental margin of India. High (87Sr/86Sr)t (ratio at time of deposition), negative εNd and high concentrations of large-ion lithophile elements (LILEs) indicate the upper continental source. Ratios of Nb/Ta and Zr/Hf suggest sedimentary and felsic igneous sources of sediments. The moderate to high concentration of La, Th and Sc, light rare earth elements (LREE-) enrichment, weak negative Eu anomalies and the relationship between εNd(0) and Th/Sc indicate the dominantly felsic composition of source rocks. However, low contents of Th, low values of (87Sr/86Sr)t and depleted mantle model age TDM < 1600 Ma indicate input from a younger mafic source. Increasing concentrations of Zr, Hf and Nd isotopes and a gradual increase in mean TDM from the older to the younger formations indicate erosional unroofing at the source terrain. The increasing (87Sr/86Sr)t through time relates to increased weathering of the source rock. The overwhelmingly southwesterly palaeocurrent direction of current-generated sedimentary structures, and the mean TDM ages trace suggest source areas of the Kutch Basin to Precambrian rocks in the north and NE of this basin. The TDM ages highlight the dominance of late Palaeoproterozoic source rocks. Nd isotope composition indicates that Proterozoic rocks of Marwar Supergroup and Erinpura Granite, in particular, served as main sediment contributors for the Mesozoic sediments in Kutch. We therefore conclude that the Mesozoic sediments in the Kutch Basin are predominantly of late Palaeoproterozoic age with lesser inputs from rocks of early Mesoproterozoic and early Palaeoproterozoic age.
- Published
- 2020
26. Role of Composition and Depth on Pore Attributes of Barakar Formation Gas Shales of Ib Valley, India, Using a Combination of Low-Pressure Sorption and Image Analysis
- Author
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Vikram Vishal, Asim Debbarma, M. K. Mishra, Debanjan Chandra, Santanu Banerjee, and S. P. Pradhan
- Subjects
Shale gas ,General Chemical Engineering ,Energy Engineering and Power Technology ,Mineralogy ,Sorption ,02 engineering and technology ,021001 nanoscience & nanotechnology ,Fuel Technology ,020401 chemical engineering ,Composition (visual arts) ,0204 chemical engineering ,0210 nano-technology ,Oil shale ,Geology - Abstract
Pore characterization of shale has gained attention over the years as it provides a good estimate of the total storage capacity of a gas shale reservoir. Ib Valley is a potential shale gas reservoi...
- Published
- 2020
27. Detrital zircon and monazite track the source of Mesozoic sediments in Kutch to rocks of Late Neoproterozoic and Early Palaeozoic orogenies in northern India
- Author
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Kaushik Das, Angana Chaudhuri, Santanu Banerjee, and Ian C.W. Fitzsimons
- Subjects
010504 meteorology & atmospheric sciences ,Metamorphic rock ,Geochemistry ,Geology ,Orogeny ,010502 geochemistry & geophysics ,01 natural sciences ,Peralkaline rock ,Petrography ,Sedimentary depositional environment ,Source rock ,Clastic rock ,0105 earth and related environmental sciences ,Zircon - Abstract
Detrital zircon and monazite dating of clastic rocks in the Mesozoic Kutch Basin at the western continental margin of India reveals predominant sediment derivation from rocks of Neoproterozoic Pan-African orogeny, followed by those of Cambro-Ordovician Bhimphedian (or Kurgiakh) orogeny and 850–1000 Ma rocks, with subordinate input from rocks of 700–800 Ma, 1500–1600 Ma, 2400–2500 Ma and 2800–3300 Ma. This finding refutes the existing idea regarding the predominant Mesoproterozoic source inferred for this basin. The dominance of southwesterly palaeocurrent data of Mesozoic rocks in Kutch Basin rules out sediment supply from south or west. Th/U ratios of detrital zircon grains indicate predominantly magmatic and subordinately metamorphic source rock. Petrographic data, particularly the QFR plot supports this interpretation of source rock. Rocks belonging to the Pan-African orogeny are poorly exposed in northwestern India while isolated outcrops of peralkaline granites in the Himalayan region bear testimony of the Bhimphedian orogeny. While the paucity of records of the Pan-African orogeny in western India possibly relates to either burial under the Deccan Flood Basalts or extensive erosion during Mesozoic greenhouse climate, the dearth of rocks of Bhimphedian orogeny results from its occurrence along the present-day Himalayan thrust belt. The absence of detrital zircon grains younger than 458 Ma indicates that post-Ordovician tectono-thermal events skipped the source area. The large gap between youngest detrital zircon and the depositional age of the Mesozoic sediments, suggests long-distance sediment transport as well as sediment recycling. This study, therefore, indicates the existence of widespread younger magmatic rocks to the north during the deposition of Mesozoic of Kutch.
- Published
- 2020
28. Microbial Mat Structures and role of microbes in Precambrian siliciclastic sedimentation: Evidence from Indian Proterozoic basins
- Author
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Partha Pratim Chakraborty, Subir Kumar Sarkar, and Santanu Banerjee
- Subjects
Precambrian ,Proterozoic ,Geochemistry ,General Earth and Planetary Sciences ,Siliciclastic ,Microbial mat ,Sedimentation ,Geology - Published
- 2020
29. Thermal Memory Response in Magneto-thermoelastic Medium Having Long Cylindrical Cavity
- Author
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Soumen Shaw, Basudeb Mukhopadhyay, and Santanu Banerjee
- Subjects
Physics ,020303 mechanical engineering & transports ,Thermoelastic damping ,010504 meteorology & atmospheric sciences ,0203 mechanical engineering ,Thermal ,02 engineering and technology ,Electrical and Electronic Engineering ,Composite material ,01 natural sciences ,Magneto ,0105 earth and related environmental sciences - Abstract
The present paper deals with the memory response on thermal disturbances emanating from a cylindrical cavity in an unbounded thermoelastic solid. Here we have theoretically demonstrated the memory response of thermal disturbances in the generalized magneto-thermo-elastic materials. Firstly, the characteristics of thermoelastic disturbances originated from the cavity in an unbounded elastic solid under the light of generalized magnetothermoelasticity theory with memory dependent derivatives (MDD). For numerical computation, cylindrical-polar coordinate system with radial symmetry subjected to two different types of heat sources into the cavity are considered. An integral transform method and, while in inverse transformation, an efficient and pragmatic NILT (Numerical Inverse Laplace Transform) is adopted. Finally, parameter studies are performed to evaluate the effect of the kernel function and time delay. For thermal wave the results show appreciable differences with those in the usual magneto-thermoelasticity theory.
- Published
- 2020
30. MECHANISM OF CIGARETTE SMOKE - INDUCED CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD)
- Author
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SANTANU BANERJEE
- Subjects
Chronic Obstructive Pulmonary Diseases (Copd) Cigarette Smoke (Cs) Lung Oxidative Stress Inflammation Airway-Remodeling ,medicine.medical_specialty ,COPD ,Mechanism (biology) ,business.industry ,Internal medicine ,Cardiology ,medicine ,Cigarette smoke ,Pulmonary disease ,medicine.disease ,business ,respiratory tract diseases - Abstract
Chronic Obstructive Pulmonary Diseases (COPD) is currently the third leading cause of death worldwide. COPD causes great burden to society by contributing in morbidity and productivity loss. Cigarette smoking is the primary reason for COPD in smokers. In spite of the several initiatives of the national and international public health organizations for quitting smoking, number of smokers are increasing in low- and middle-income countries continuously. For the prevention and morbidity management of this treatable disease, understanding of the pathogenic events orchestrated by cigarette smoke (CS) is required. In smokers, COPD is caused by the constant exposure of lung to harmful components of CS. Oxidative stress plays the central role in CS-induced COPD pathogenesis in smokers along with other important components of COPD pathogenesis, such as lung injury, lung inflammation, protease-antiprotease imbalance, small airway remodeling and apoptosis. In this review we tried to briefly summarize the mechanisms behind the CS-induced pathogenesis for COPD which follow a complex network of events.
- Published
- 2020
31. A review of biotic signatures within the Precambrian Vindhyan Supergroup: Implications on evolution of microbial and metazoan life on Earth
- Author
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Santanu Banerjee, Subir Kumar Sarkar, and Adrita Choudhuri
- Subjects
Precambrian ,Geophysics ,Earth science ,Geology ,Earth (chemistry) ,Supergroup - Published
- 2020
32. Compositional evolution of siliciclastic sediments recording the tectonic stability of a pericratonic rift: Mesozoic Kutch Basin, western India
- Author
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Santanu Banerjee, Angana Chaudhuri, and Gaurav Chauhan
- Subjects
Rift ,Felsic ,010504 meteorology & atmospheric sciences ,Stratigraphy ,Archean ,Geochemistry ,Geology ,010502 geochemistry & geophysics ,Oceanography ,01 natural sciences ,Geophysics ,Source rock ,Economic Geology ,Siliciclastic ,Sedimentary rock ,Mafic ,0105 earth and related environmental sciences ,Zircon - Abstract
This study presents a combined petrographical and geochemical investigation to track the compositional changes in the Mesozoic sedimentary record during the evolution of the pericratonic rift basin of Kutch. The Mesozoic sequence of the proven petroliferous basin of Kutch, representing ~3000 m thick siliciclastic and carbonate deposition within a time frame of ~70 Ma, consists of Jhurio, Jhumara, Jhuran and Bhuj formations in ascending order of succession. The dominance of arkosic sandstones and the abundance of zircon and monazite indicate predominantly felsic source rocks. The concentration of individual trace elements such as Th, Sc, Zr, V, Ni and ratios like Th/Sc, Cr/V, Y/Ni, Th/Co, La/Sc support the predominantly felsic source rock. The LREE enrichment and the negative Eu anomaly corroborate the predominantly felsic source. However, concentrations of V, Ni and Ti reveal the mafic input in older stratigraphic units. While (GdN/YbN) indicates dominant post-Archean source across the Mesozoic succession, younger stratigraphic units reveal contributions from the Archean rocks, from Nagar Parkar and Aravalli highland regions. The CIA values suggest intermediate to intense weathering, while the ICV data record a shift from immature sediments in the older formations to mature and recycled types in the younger formations. The high value of Zr/Sc as well a high content of Hf reflects the addition of zircon by recycling or by erosional unroofing of older continental rocks. Major oxide (SiO2, Na2O and K2O) and trace elements (La, Th and Hf) bear the passive margin setting for the Kutch Basin during the Mesozoic. The decrease in feldspar content (in sandstones), increase in the concentration of Zr and Hf (in shale) and a decrease in values of ICV from older to younger stratigraphic units corresponds to the compositional evolution related to increased stability of the Kutch basin during the transition from early syn-rift to post-rift.
- Published
- 2020
33. Memory response on thermoelastic deformation in a solid half-space with a cylindrical hole
- Author
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Santanu Banerjee, Basudeb Mukhopadhyay, and Soumen Shaw
- Subjects
Materials science ,Mechanical Engineering ,General Mathematics ,Aerospace Engineering ,020101 civil engineering ,Ocean Engineering ,02 engineering and technology ,Mechanics ,Deformation (meteorology) ,Half-space ,Dissipation ,Condensed Matter Physics ,0201 civil engineering ,020303 mechanical engineering & transports ,Thermoelastic damping ,0203 mechanical engineering ,Mechanics of Materials ,Automotive Engineering ,Thermal wave ,Civil and Structural Engineering - Abstract
The present article deals with the memory response on thermal wave propagation emanating from a cylindrical hole in an unbounded thermoelastic solid. Here, we have theoretically demonstrated two as...
- Published
- 2019
34. Acetylcholinesterase Inhibitor Pyridostigmine Bromide Attenuates Gut Pathology and Bacterial Dysbiosis in a Murine Model of Ulcerative Colitis
- Author
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Shashi P. Singh, Santanu Banerjee, Veena Raizada, Sabita Roy, Mohan L. Sopori, Hitendra S. Chand, and Hemant S. Agarwal
- Subjects
Colon ,Physiology ,medicine.drug_class ,Anti-Inflammatory Agents ,Gut flora ,Pharmacology ,GPI-Linked Proteins ,digestive system ,Inflammatory bowel disease ,Nicotine ,03 medical and health sciences ,Th2 Cells ,0302 clinical medicine ,medicine ,Animals ,Mucin-2 ,biology ,Chemistry ,Gastroenterology ,biology.organism_classification ,medicine.disease ,Ulcerative colitis ,digestive system diseases ,Gastrointestinal Microbiome ,Disease Models, Animal ,Acetylcholinesterase inhibitor ,030220 oncology & carcinogenesis ,Acetylcholinesterase ,Cytokines ,Dysbiosis ,Colitis, Ulcerative ,030211 gastroenterology & hepatology ,Pyridostigmine Bromide ,Cholinesterase Inhibitors ,Inflammation Mediators ,Acetylcholine ,medicine.drug - Abstract
Ulcerative colitis (UC) is a Th2 inflammatory bowel disease characterized by increased IL-5 and IL-13 expression, eosinophilic/neutrophilic infiltration, decreased mucus production, impaired epithelial barrier, and bacterial dysbiosis of the colon. Acetylcholine and nicotine stimulate mucus production and suppress Th2 inflammation through nicotinic receptors in lungs but UC is rarely observed in smokers and the mechanism of the protection is unclear. In order to evaluate whether acetylcholine can ameliorate UC-associated pathologies, we employed a mouse model of dextran sodium sulfate (DSS)-induced UC-like conditions, and a group of mice were treated with Pyridostigmine bromide (PB) to increase acetylcholine availability. The effects on colonic tissue morphology, Th2 inflammatory factors, MUC2 mucin, and gut microbiota were analyzed. DSS challenge damaged the murine colonic architecture, reduced the MUC2 mucin and the tight-junction protein ZO-1. The PB treatment significantly attenuated these DSS-induced responses along with the eosinophilic infiltration and the pro-Th2 inflammatory factors. Moreover, PB inhibited the DSS-induced loss of commensal Clostridia and Flavobacteria, and the gain of pathogenic Erysipelotrichia and Fusobacteria. Together, these data suggest that in colons of a murine model, PB promotes MUC2 synthesis, suppresses Th2 inflammation and attenuates bacterial dysbiosis therefore, PB has a therapeutic potential in UC.
- Published
- 2019
35. Paleoenvironmental Conditions during the Paleocene–Eocene Transition Imprinted within the Glauconitic Giral Member of the Barmer Basin, India
- Author
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Sher Singh Meena, Tathagata Roy Choudhury, Sonal Khanolkar, and Santanu Banerjee
- Subjects
PETM ,lignite ,authigenic mineral formation ,shallow marine ,glauconite ,Barmer Basin ,iron sequestration ,Geology ,Geotechnical Engineering and Engineering Geology ,Mineralogy ,QE351-399.2 - Abstract
The roughly 6 m thick limestone–green shale alternation within the lignite-bearing Giral Member of the Barmer Basin corresponds to a marine flooding event immediately after the Paleocene–Eocene transition. A detailed characterization of the glauconite using Electron Probe Micro Analyzer (EPMA), X-Ray Diffraction (XRD), Mössbauer and Field Emission Gun-Scanning Electron Microscope (FEG-SEM) reveals its origin in the backdrop of prevailing warm climatic conditions. The glauconite pellets vary from fine silt-sized to coarse sand-sized pellets, often reaching ~60% of the rock by volume. Mineralogical investigation reveals a ‘nascent’ to ‘slightly evolved’ character of the marginal marine-originated glauconite showing considerable interstratification. The chemical composition of the glauconite is unusual with a high Al2O3 (>10 wt%) and moderately high Fe2O3(total) contents (>15 wt%). While the K2O content of these glauconites is low, the interlayer sites are atypically rich in Na2O, frequently occupying ~33% of the total interlayer sites. The Mössbauer spectrum indicates 10% of the total iron is in ferrous form. High tetrahedral Al3+ of these glauconites suggests a high-alumina substrate that transformed to glauconite by octahedral Al-for-Fe substitution followed by the addition of K into the interlayer structure. The unusually high Na2O suggests the possibility of a soda-rich pore water formed by the dissolution of alkaline volcanic minerals. The Giral glauconite formation could have been a part of the major contributors in the Fe-sequestration cycle in the Early Eocene shelves. Warm climate during the Early Eocene time favored the glauconitization because of the enhanced supply of Fe, Al, and Si and proliferation of an oxygen-depleted depositional environment.
- Published
- 2021
- Full Text
- View/download PDF
36. The Gut–Brain Axis in the Context of Gut Microbiome and Its Metabolites
- Author
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Santanu Banerjee
- Subjects
Gut–brain axis ,Context (language use) ,Biology ,Neuroscience ,Gut microbiome - Published
- 2021
37. Origin of ooids, peloids and micro-oncoids of marine ironstone deposits in Western Siberia (Russia)
- Author
-
Maxim Rudmin, Santanu Banerjee, Prokopiy Maximov, Andrey Novoselov, Yaroslav Trubin, Pavel Smirnov, Adam Abersteiner, Dongjie Tang, and Alexey Mazurov
- Subjects
Geology ,Earth-Surface Processes - Published
- 2022
38. Depositional Conditions of Cretaceous Ironstones Deposit in the Chulym-Yenisey Basin (Western Siberia)
- Author
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Aleksey Ruban, Santanu Banerjee, Aigerim Dauletova, and Maxim Rudmin
- Subjects
paleoenvironmental conditions ,аутигенные минералы ,Chamosite ,месторождения ,осадконакопление ,отложения ,Geochemistry ,ironstones ,engineering.material ,Feldspar ,Siderite ,chemistry.chemical_compound ,iron geochemical cycle ,Geology ,Authigenic ,Mineralogy ,Geotechnical Engineering and Engineering Geology ,железо ,Diagenesis ,continental deposits ,chemistry ,Late Cretaceous ,visual_art ,Illite ,authigenic minerals ,engineering ,visual_art.visual_art_medium ,iron source ,геохимические циклы ,Pyrite ,Chlorite group ,QE351-399.2 - Abstract
This study reconstructs the depositional conditions of ironstones within the Chulym-Yenisey basin and assesses the iron source. The detrital minerals of the studied deposits include quartz and feldspar. The authigenic minerals are goethite, siderite, aragonite, dolomite, calcite, apatite, barite, and pyrite. The clay components include minerals of the chlorite group (possible chamosite), nontronite, kaolinite, illite, and beidellite. Local bacterial sulfate reduction led to the formation of pyrite framboids in siltstone layers. The subsequent diagenetic iron reduction promoted the formation of chamosite from siderite. The goethite precipitation occurred in an oxidic aqueous environment. The Cretaceous continental sediments of the Ilek and Kia Formations of the Chulym-Yenisei depression consist of fine- and medium-grained, cross-stratified, poorly sorted litho-feldspatho-quartzose sandstones of fluvial channel origin alternating with bluish-gray siltstones and ironstones of floodplain–lacustrine–bog origin. Thin layers of iron-bearing rocks within siltstones formed in meromictic waters. The changes in geochemical proxies demonstrate fluctuations of paleoenvironmental conditions within the Cretaceous sequence. Siltstones and sandstones formed under humid and arid conditions, respectively. The primary iron source for sediments of the Chulym-Yenisey depression was determined as volcanogenic and igneous rocks of the Altai-Sayan mountainous region.
- Published
- 2021
- Full Text
- View/download PDF
39. Impact of green clay authigenesis on K–Mg–Fe sequestration in marine settings
- Author
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György Czuppon, Martin Dietzel, Thomas Zack, Ulrike Moser, Esther Scheiblhofer, Andre Baldermann, Stefan Löhr, Santanu Banerjee, Juraj Farkas, and Nicky M. Wright
- Abstract
Retrograde clay mineral reactions (i.e., reverse weathering), including glauconite formation, are first-order controls on element (re)cycling vs sequestration in modern and ancient marine sediments. Here, we report substantial K–Mg–Fe sequestration by glauconite formation in shallow marine settings from the Triassic to the Holocene, averaging 4 ± 3 mmol K·cm−²·kyr− 1, 4 ± 2 mmol Mg·cm−²·kyr− 1 and 10 ± 6 mmol Fe·cm−²·kyr− 1, which is ~ 2 orders of magnitude higher compared to deep-sea settings. Upscaling of glauconite abundances in shallow-water (− 1, ~ 0.04–0.06 Tmol Mg·yr− 1 and ~ 0.11–0.14 Tmol Fe·yr− 1. We conclude that authigenic clay elemental uptake had a large impact on the global marine K, Mg and Fe cycles throughout Earth`s history, in particular during ‘greenhouse’ periods with sea level highstand. Quantifying authigenic clay formation is key for better understanding past and present geochemical cycling in marine sediments.
- Published
- 2021
40. Impact of green clay authigenesis on element sequestration in marine settings
- Author
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Andre Baldermann, Santanu Banerjee, György Czuppon, Martin Dietzel, Juraj Farkaš, Stefan Lӧhr, Ulrike Moser, Esther Scheiblhofer, Nicky M. Wright, and Thomas Zack
- Subjects
Geologic Sediments ,Minerals ,Multidisciplinary ,General Physics and Astronomy ,Clay ,General Chemistry ,General Biochemistry, Genetics and Molecular Biology - Abstract
Retrograde clay mineral reactions (reverse weathering), including glauconite formation, are first-order controls on element sequestration in marine sediments. Here, we report substantial element sequestration by glauconite formation in shallow marine settings from the Triassic to the Holocene, averaging 3 ± 2 mmol·cm−²·kyr−1 for K, Mg and Al, 16 ± 9 mmol·cm−²·kyr−1 for Si and 6 ± 3 mmol·cm−²·kyr−1 for Fe, which is ~2 orders of magnitude higher than estimates for deep-sea settings. Upscaling of glauconite abundances in shallow-water (0–200 m) environments predicts a present-day global uptake of ~≤ 0.1 Tmol·yr−1 of K, Mg and Al, and ~0.1–0.4 Tmol·yr−1 of Fe and Si, which is ~half of the estimated Mesozoic elemental flux. Clay mineral authigenesis had a large impact on the global marine element cycles throughout Earth’s history, in particular during ‘greenhouse’ periods with sea level highstand, and is key for better understanding past and present geochemical cycling in marine sediments.
- Published
- 2021
41. Age Associated Microbiome and Microbial Metabolites Modulation and Its Association With Systemic Inflammation in a Rhesus Macaque Model
- Author
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Suresh Pallikkuth, Roberto Mendez, Kyle Russell, Tirupataiah Sirupangi, Daniel Kvistad, Rajendra Pahwa, Francois Villinger, Santanu Banerjee, and Savita Pahwa
- Subjects
Male ,Aging ,Immunology ,Inflammation ,microbiome and metabolites ,Systemic inflammation ,chemistry.chemical_compound ,Feces ,Immune system ,Immunity ,Tandem Mass Spectrometry ,medicine ,Immunology and Allergy ,Animals ,Microbiome ,immunity and microbiome ,Symbiosis ,Original Research ,age and immunity ,biology ,Bacteria ,Tumor Necrosis Factor-alpha ,Neopterin ,Immunosenescence ,RC581-607 ,biology.organism_classification ,Macaca mulatta ,Gastrointestinal Microbiome ,age and microbes ,Rhesus macaque ,Disease Models, Animal ,C-Reactive Protein ,age and metabolites ,chemistry ,Cytokines ,Dysbiosis ,Female ,medicine.symptom ,Immunologic diseases. Allergy - Abstract
Aging is associated with declining immunity and inflammation as well as alterations in the gut microbiome with a decrease of beneficial microbes and increase in pathogenic ones. The aim of this study was to investigate the age associated gut microbiome in relation to immunologic and metabolic profile in a non-human primate (NHP) model. 12 geriatric (age 19-24 years) and 4 young adult (age 3-4 years) Rhesus macaques were included in this study. Immune cell subsets were characterized in peripheral blood mononuclear cells (PBMC) by flow cytometry and plasma cytokines levels were determined by bead based multiplex cytokine analysis. Stool samples were collected by ileal loop and investigated for microbiome analysis by shotgun metagenomics. Serum, gut microbial lysate, and microbe-free fecal extract were subjected to metabolomic analysis by mass-spectrometry. Our results showed that the gut microbiome in geriatric animals had higher abundance of Archaeal and Proteobacterial species and lower Firmicutes than the young adults. Highly abundant microbes in the geriatric animals showed a direct association with plasma biomarkers of inflammation and immune activation such as neopterin, CRP, TNF, IL-2, IL-6, IL-8 and IFN-γ. Significant enrichment of metabolites that contribute to inflammatory and cytotoxic pathways was observed in serum and feces of geriatric animals compared to the young adults. We conclude that aging NHP undergo immunosenescence and age associated alterations in the gut microbiome that has a distinct metabolic profile. Aging NHP can serve as a model for investigating the relationship of the gut microbiome to particular age-associated comorbidities and for strategies aimed at modulating the microbiome.
- Published
- 2021
42. A study of iron carbonates and clay minerals for understanding the origin of marine ooidal ironstone deposits
- Author
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Maxim Rudmin, Santanu Banerjee, Ekaterina Sinkina, Alexey Ruban, Natalia Kalinina, and Pavel Smirnov
- Subjects
Geophysics ,Stratigraphy ,Economic Geology ,Geology ,Oceanography - Published
- 2022
43. Glauconite authigenesis during the warm climatic events of Paleogene: Case studies from shallow marine sections of Western India
- Author
-
Tathagata Roy Choudhury, Sonal Khanolkar, and Santanu Banerjee
- Subjects
Global and Planetary Change ,Oceanography - Published
- 2022
44. A Monograph on Potential Geoparks of India, D. Rajasekhar Reddy (Editor), Published by Indian National Trust for Art and Culture Heritage, 266p. (Price not mentioned)
- Author
-
Santanu Banerjee
- Subjects
Geology - Published
- 2022
45. High Mg-glauconite in the Campanian Duwi Formation of Abu Tartur Plateau, Egypt and its implications
- Author
-
Emad Nagm, Sherif Farouk, Santanu Banerjee, Tathagata Roy Choudhury, and Sher Singh Meena
- Subjects
010504 meteorology & atmospheric sciences ,Geochemistry ,Geology ,Authigenic ,engineering.material ,010502 geochemistry & geophysics ,01 natural sciences ,Cretaceous ,Transition zone ,Dolomitization ,engineering ,Transgressive ,Clay minerals ,Oil shale ,Glauconite ,0105 earth and related environmental sciences ,Earth-Surface Processes - Abstract
This study presents a detailed crystallo-chemical characterization of glauconites occurring at different stratigraphic intervals within the phosphorite-bearing Campanian Duwi Formation. While authigenic glauconites occur within the shallow marine, transgressive deposits of Abu Tartur Phosphate and Maghrabi Shale Members in the Campanian Duwi Formation, allogenic variety occurs within the regressive deposits at the top of the Liffiya Shale Member. Nascent to slightly evolved, shallow-marine originated authigenic glauconites are distinct by a high content of MgO. A good correlation between K2O and Fe2O3(total) contents of glauconites in the Maghrabi Shale supports ‘layer lattice’ theory while a combination of ‘layer lattice’ and ‘verdissement’ theories explain the origin of other glauconites within the Duwi Formation. X-Ray Diffraction studies reveal a ‘true’ di-octahedral nature and 1M ordering of the glauconite pellets with smectite inter-stratification. Mossbauer spectroscopic study reveals Fe3+ as the dominant cation in the octahedral site that preferentially occupies the less distorted cis M(2) sites. Glauconites acquire a high Mg-content because of the passage of Mg- and Ca-rich fluid that leads to extensive dolomitization. Glauconites form at the transition zone between black shale and phosphate, representing oxygen-depleted conditions. Similar shallow marine glauconites occur all along the paleo-Tethyan margin during the Late Cretaceous time.
- Published
- 2019
46. The Microbiome and Ocular Surface Disease
- Author
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Arjun Watane, Kara M. Cavuoto, Santanu Banerjee, and Anat Galor
- Subjects
0301 basic medicine ,genetic structures ,biology ,business.industry ,Firmicutes ,Disease ,medicine.disease ,biology.organism_classification ,eye diseases ,Keratitis ,03 medical and health sciences ,Ophthalmology ,030104 developmental biology ,0302 clinical medicine ,Immunology ,030221 ophthalmology & optometry ,medicine ,sense organs ,Microbiome ,Proteobacteria ,Blepharitis ,business ,Dysbiosis ,Uveitis - Abstract
The human body lives in a symbiotic relationship with the bacteria, viruses, fungi, and protozoa that make up the microbiome. In this review, we discuss the compositions of the gut and ocular surface microbiomes in relationship to health and disease. The gut microbiome is dominated by Firmicutes, whereas the ocular surface is dominated by Proteobacteria. The compositions of the microbiome are similar between individuals at the phyla level, but differ at the genus level. Alterations in the microbiome have been associated with disease. For example, ocular diseases such as uveitis, dry eye, and keratitis have been associated with gut dysbiosis. In addition, ocular surface dysbiosis has been reported in diseases including dry eye, blepharitis, keratitis, and diabetic retinopathy. Compositions of the gut and ocular surface microbiomes have been found to differ in disease states compared with controls. Further understanding of dysbiosis specific to a disease is needed to target these surfaces for therapeutic strategies.
- Published
- 2019
47. Unusual seawater composition of the Late Cretaceous Tethys imprinted in glauconite of Narmada basin, central India
- Author
-
Udita Bansal, Kanchan Pande, Dhiren Kumar Ruidas, and Santanu Banerjee
- Subjects
Sedimentary depositional environment ,engineering ,Geochemistry ,Geology ,Weathering ,Authigenic ,Transgressive ,engineering.material ,Structural basin ,Glauconite ,Cretaceous ,Diagenesis - Abstract
A detailed investigation of a glauconite bed within the Late Cretaceous Bryozoan Limestone Formation of the Bagh Group in central India, as well as the study of existing records, reveals the existence of a ‘glauconitic sea’ along the margins of the Palaeo-Tethys Ocean during the Late Cretaceous Epoch. The authigenic green mineral formed abundantly on shallow seafloors unlike in its modern, deep-sea counterpart. We present an integrated petrographical, geochemical and mineralogical investigation of the glauconite within Late Cretaceous transgressive deposits to highlight its unique geochemistry with moderate Fe2O3 and high Al2O3, SiO2, MgO as well as K2O contents. X-ray diffractional parameters identify the ‘evolved to high evolved’ nature of the glauconite while Mössbauer spectroscopic study reveals the dominance of Fe3+ compared to Fe2+ in the atomic structure. The rare earth elements (REE) pattern of glauconite reveals moderate light-REE/heavy-REE (LREE/HREE) fractionation and weak negative Eu anomaly. The Ce anomaly of the glauconite indicates a sub-oxic diagenetic condition. We propose that Late Cretaceous glauconites formed within a shallow marine depositional setting across the Tethyan belt because of enhanced supply of K, Si, Al, Fe, Mg cations through continental weathering under the extant greenhouse climate.
- Published
- 2019
48. A comparative study of surface layer formation in Ni-based alloys with varying Cr contents exposed to high temperature fluoride environment
- Author
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Santanu Banerjee, Rumu H. Banerjee, Ashok Arya, and Vishal Singh
- Subjects
Nuclear and High Energy Physics ,Materials science ,Metallurgy ,Alloy ,Oxide ,FLiNaK ,02 engineering and technology ,engineering.material ,021001 nanoscience & nanotechnology ,01 natural sciences ,010305 fluids & plasmas ,Corrosion ,chemistry.chemical_compound ,Nuclear Energy and Engineering ,chemistry ,0103 physical sciences ,engineering ,Galvanic cell ,Mixed oxide ,General Materials Science ,Surface layer ,0210 nano-technology ,Fluoride - Abstract
Microstructural and surface characterization of Ni-based alloys viz. Alloy 690, Alloy 693 and Ni-17 wt.% Mo- 7wt.% Cr exposed to molten FLiNaK salt under air atmosphere at 973 K was carried out. Patches of mixed oxide layers of type NiO + Cr2O3, NiO + Al2O3 +Cr2O3 and MoO3 + NiO + Cr2O3 were observed for Alloy 690, alloy 693 and Ni-Mo-Cr alloy, respectively. Corrosion susceptibility index and calculated Cr diffusivity in the alloys followed the order: Alloy 690 > Alloy 693>Ni-Cr-Mo alloy. The oxide layers developed are only partially protective as they form a galvanic micro-couple with exposed surface which makes the later more prone to attack. The lower Cr depletion in case of Ni-Mo-Cr alloy as compared to Alloy 690 and 693 can be attributed to the fact that MoO3 layer is formed over the areas devoid of oxide patches which may prevent/reduce galvanic coupling between Ni-,Cr-rich oxides and exposed surface.
- Published
- 2019
49. ER stress sensor, glucose regulatory protein 78 (GRP78) regulates redox status in pancreatic cancer thereby maintaining 'stemness'
- Author
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Nikita S. Sharma, Patricia Dauer, Sulagna Banerjee, Brittany Durden, Ashok K. Saluja, Santanu Banerjee, Roey Hadad, Vineet Gupta, and Vikas Dudeja
- Subjects
0301 basic medicine ,Cancer Research ,Immunology ,Population ,Mice, Nude ,Tumor initiation ,Biology ,Transfection ,Article ,Metastasis ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,Mice ,0302 clinical medicine ,Downregulation and upregulation ,Cancer stem cell ,Pancreatic cancer ,Cell Line, Tumor ,medicine ,Animals ,Humans ,Neoplasm Invasiveness ,Cell Self Renewal ,lcsh:QH573-671 ,education ,Endoplasmic Reticulum Chaperone BiP ,Heat-Shock Proteins ,Cell Proliferation ,education.field_of_study ,lcsh:Cytology ,Cancer ,Cell Biology ,medicine.disease ,Endoplasmic Reticulum Stress ,Lipid Metabolism ,3. Good health ,Tumor Burden ,Pancreatic Neoplasms ,Oxidative Stress ,030104 developmental biology ,030220 oncology & carcinogenesis ,Gene Knockdown Techniques ,Unfolded protein response ,Cancer research ,Unfolded Protein Response ,Heterografts ,Reactive Oxygen Species ,Oxidation-Reduction ,DNA Damage - Abstract
Endoplasmic reticulum (ER) stress and the unfolded protein response (UPR) signaling have been shown to be dysregulated in multiple cancer types. Glucose regulatory protein 78 (GRP78), the master regulator of the UPR, plays a role in proliferation, invasion, and metastasis in cancer. Cancer stem cells (CSCs) make up a crucial component of the tumor heterogeneity in pancreatic cancer, as well as other cancers. “Stemness” in pancreatic cancer defines a population of cells within the tumor that have increased therapeutic resistance as well as survival advantage. In the current study, we investigated how GRP78 was responsible for maintaining “stemness” in pancreatic cancer thereby contributing to its aggressive biology. We determined that GRP78 downregulation decreased clonogenicity and self-renewal properties in pancreatic cancer cell lines in vitro. In vivo studies resulted in delayed tumor initiation frequency, as well as smaller tumor volume in the shGRP78 groups. Additionally, downregulation of GRP78 resulted in dysregulated fatty acid metabolism in pancreatic tumors as well as the cells. Further, our results showed that shGRP78 dysregulates multiple transcriptomic and proteomic pathways that involve DNA damage, oxidative stress, and cell death, that were reversed upon treatment with a ROS inhibitor, N-acetylcysteine. This study thus demonstrates for the first time that the heightened UPR in pancreatic cancer may be responsible for maintenance of the “stemness” properties in these cells that are attributed to aggressive properties like chemoresistance and metastasis.
- Published
- 2019
50. Origin of ooidal ironstones in relation to warming events: Cretaceous-Eocene Bakchar deposit, south-east Western Siberia
- Author
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Aleksey Mazurov, Santanu Banerjee, and Maxim Rudmin
- Subjects
Greigite ,010504 meteorology & atmospheric sciences ,Stratigraphy ,Trace element ,Geochemistry ,Geology ,Authigenic ,engineering.material ,010502 geochemistry & geophysics ,Oceanography ,01 natural sciences ,Sedimentary depositional environment ,Siderite ,chemistry.chemical_compound ,Ironstone ,Geophysics ,chemistry ,Anaerobic oxidation of methane ,engineering ,Economic Geology ,Pyrrhotite ,0105 earth and related environmental sciences - Abstract
An integrated study involving petrographical, mineralogical and geochemical investigations proposes the origin of the Bakchar ironstone deposit by upward migration of a mixture of Fe-rich brine and hydrothermal fluid through marine sediments. Trace element concentrations of the ironstone deposits rule out continental derivation of Fe, while high REE concentrations indicate mixed hydrogeneous and hydrothermal source. Three main types of ironstone within the Bakchar deposit are characterized by distinct mineralogical assemblage of authigenic minerals corresponding to oxic, methanic and weakly sulfidic dysoxic conditions. Changing redox conditions of the depositional environment, methane seepage in warm seawater and availability of iron influx possibly determined the final mineralogy of three varieties of ironstones. The association of siderite with ferrimagnetic sulfides like greigite and pyrrhotite in type-1 ore indicate anaerobic oxidation of methane with limited bacterial sulfate reduction. The ironstone deposits of Narym, Kolpashevo and Bakchar are contemporaneous with geological events like ocean anoxic event 3 (OAE-3), Cretaceous-Paleogene (K-Pg) boundary and Palaeocene-Eocene Thermal Maximum (PETM), respectively, all corresponding to warm seawater conditions.
- Published
- 2019
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