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1.
J Environ Manage ; 324: 116297, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36174475

RESUMO

Pongamia pinnata (L.) Pierre (Pongamia) is a tree native to Southeast Asia. Recently, interest in Pongamia focused on its potential as a biofuel source as its seeds contain around 40% oil. However, Pongamia has multiple applications beyond biofuel production. It is a legume, can form symbiotic associations with mycorrhizal fungi, has been shown to be tolerant to drought, salinity, and heavy metals in soil, and has potential to mitigate climate change. Additionally, Pongamia oil has medicinal properties, can be used as biopesticide, insect repellent, to produce soap, and as a source of edible grade vegetable oil. The seed cake can be used as a source of bioenergy, food and feed protein, and organic fertiliser, and the flowers are a good source of pollen and nectar. Pongamia can also bring socio-economic benefits as its ability to restore degraded and contaminated land provides opportunities for local communities through novel valorisation pathways. These multiple applications have potential to form part of a circular bioeconomy in line with sustainable development goals. Although research on the multiple applications of Pongamia has grown considerably, knowledge gaps remain and these need to be addressed so that the full potential of Pongamia can be achieved. Further understanding of the mechanisms underlying its resilience to abiotic stresses, phytoremediation potential and biotic interactions should be a priority, and co-ordinated breeding efforts will be key. Here, we critically review the available literature on Pongamia and highlight gaps in knowledge in which future research should focus on to ensure that the full potential of this versatile tree can be achieved. We conclude that Pongamia can potentially form part of a circular bioeconomy and that harnessing the multiple applications of Pongamia in a holistic manner, with collaboration among key stakeholders, is crucial for the successful application of its benefits far beyond biofuel production.


Assuntos
Millettia , Pongamia , Millettia/metabolismo , Sequestro de Carbono , Biocombustíveis , Melhoramento Vegetal , Árvores/metabolismo , Fatores Socioeconômicos
2.
Toxicol Rep ; 5: 173-182, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29387565

RESUMO

The concentration of some heavy metals: Al, Ca, K, Fe, Ti, Mg, Mn, V, Cr, Zn, Ni and Co in sediments from Pulicat Lake to Vadanemmeli along Chennai Coast, Tamil Nadu has been determined using EDXRF technique. The mean concentrations of Mg, Al, K, Ca, Ti, Fe, V, Cr, Mn, Co, Ni, and Zn were found to be 1918, 25436, 9832, 9859, 2109, 8209, 41.58, 34.14, 160.80, 2.85. 18.79 and 29.12 mg kg-1 respectively. These mean concentrations do not exceed the world crustal average. The level of pollution attributed to heavy metals was evaluated using several pollution indicators in order to determine anthropogenically derived contaminations. Enrichment Factor (EF), Geoaccumulation Index (Igeo), Contamination Factor (CF) and Pollution Load Index (PLI) were used in evaluating the contamination status of sediments. Enrichment Factors (EF) reveal the anthropogenic sources of V, Cr, Ni and Zn Geoaccumulation Index (Igeo) results reveal that the study area is not contaminated by the heavy metals. Similar results were also obtained by using pollution load index (PLI). The results of pollution indices indicates that most of the locations were not polluted by heavy metals. Multivariate statistical analysis performed using principal components and clustering techniques were used to identify the source of the heavy metals. The result of statistical procedures indicate that heavy metals in sediments are mainly of natural origin. This study provides a relatively novel technique for identifying and mapping the distribution of metal pollutants and their sources in sediment.

3.
Environ Monit Assess ; 189(8): 399, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28718095

RESUMO

A study was carried out to investigate the changes in the physicochemical and biological properties of sub-soil river water upon its storage in a man-made reservoir. Palar sub-soil and reservoir water samples were collated fortnightly for a period of 5 years (2010-2014). The open reservoir is used as a reliable raw water source for condenser cooling systems and for the demineralizing (DM) plant input of Fast Breeder Test Reactor (FBTR), Madras Atomic Power Station (MAPS), and other laboratories at Kalpakkam, southeast coast of India. Relatively high nutrient concentration was observed in the Palar sub-soil water, and a significant reduction in average concentration (µmol l-1) of phosphate (Palar 1.92; open reservoir 1.54) and nitrate (Palar 9.78; open reservoir 5.67) was observed from Palar to open reservoir. Substantial increase in pH (Palar 8.05; open reservoir 8.45), dissolved oxygen (mg l-1) (Palar 6.07; open reservoir 8.47), and chlorophyll-a (mg m-3) (Palar 1.66; open reservoir 8.43) values were noticed from the Palar sub-soil water to open reservoir water. It is concluded that sub-soil water with higher nutrient concentrations when stored openly, exposing to the sun, resulted in growth of plants, planktonic, and macrophytes, which led to substantial deterioration in water quality from its utility point of view as a condenser cooling medium and raw water input for DM plant.


Assuntos
Monitoramento Ambiental/métodos , Rios/química , Clorofila/análogos & derivados , Clorofila A , Água Doce/química , Índia , Solo , Água , Poluentes da Água/análise , Qualidade da Água , Abastecimento de Água
4.
Mar Pollut Bull ; 121(1-2): 418-424, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-28633945

RESUMO

The aim of this study was to determine the concentration of heavy metals in the sediments of Periyakalapet to Parangipettai coast, east coast of Tamil Nadu, by using energy-dispersive X-ray fluorescence (EDXRF) technique. The average heavy metal concentrations in the sediment samples were found in the order Al>Fe>Ca>Ti>K>Mg>Mn>Ba>V>Cr>Zn>La>Ni>Pb>Co>Cd>Cu. The average heavy metal concentrations were below the world crustal average. The degree of contamination by heavy metals was evaluated using pollution indices. The results of pollution indices revealed that titanium (Ti) and cadmium (Cd) were significantly enriched in sediments. Pearson correlation analysis was performed among heavy metal concentrations to know the existing relationship between them. Multivariate statistical technique was employed to identify the heavy metal pollution sources.


Assuntos
Metais Pesados/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Sedimentos Geológicos , Índia
5.
Appl Radiat Isot ; 102: 42-47, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25956221

RESUMO

The study of heavy metal pollution in coastal sediments assumes importance with respect to environmental ecology in view of the rapid industrialization and increased anthropogenic activities. The concentrations of Mg, Al, K, Ca, Ti, Fe, V, Cr, Mn, Co, Ni and Zn were measured in twenty sampling sites along the east coast of Tamilnadu, India by energy dispersive X-ray fluorescence spectroscopy (EDXRF). Natural background values were used to delineate their origin as geogenic or anthropogenic. To interpret and assess the contamination status for heavy metals in sediments, four metal pollution indices used such as an enrichment factor, a geo-accumulation index, a contamination factor and a pollution load index. Multivariate statistical methods were applied to identify the source of heavy metals. Heavy metal toxicity risk was assessed using sediment quality guidelines. The presented methodology was used to determine the anthropogenic origin of heavy metals in the sediment.

6.
Elife ; 42015 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-25905673

RESUMO

Tissue microenvironment functions as an important determinant of the inflammatory response elicited by the resident cells. Yet, the underlying molecular mechanisms remain obscure. Our systems-level analyses identified a duration code that instructs stimulus specific crosstalk between TLR4-activated canonical NF-κB pathway and lymphotoxin-ß receptor (LTßR) induced non-canonical NF-κB signaling. Indeed, LTßR costimulation synergistically enhanced the late RelA/NF-κB response to TLR4 prolonging NF-κB target gene-expressions. Concomitant LTßR signal targeted TLR4-induced newly synthesized p100, encoded by Nfkb2, for processing into p52 that not only neutralized p100 mediated inhibitions, but potently generated RelA:p52/NF-κB activity in a positive feedback loop. Finally, Nfkb2 connected lymphotoxin signal within the intestinal niche in reinforcing epithelial innate inflammatory RelA/NF-κB response to Citrobacter rodentium infection, while Nfkb2(-/-) mice succumbed to gut infections owing to stromal defects. In sum, our results suggest that signal integration via the pleiotropic NF-κB system enables tissue microenvironment derived cues in calibrating physiological responses.


Assuntos
Citrobacter rodentium/imunologia , Infecções por Enterobacteriaceae/imunologia , Imunidade Inata/genética , Inflamação/genética , NF-kappa B/genética , Transdução de Sinais/genética , Animais , Citrobacter rodentium/patogenicidade , Regulação da Expressão Gênica/imunologia , Mucosa Intestinal/imunologia , Mucosa Intestinal/microbiologia , Receptor beta de Linfotoxina/genética , Receptor beta de Linfotoxina/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , NF-kappa B/imunologia , Subunidade p52 de NF-kappa B/deficiência , Subunidade p52 de NF-kappa B/genética , Fator de Transcrição RelA/genética , Fator de Transcrição RelA/imunologia
7.
Spectrochim Acta A Mol Biomol Spectrosc ; 137: 589-600, 2015 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-25240831

RESUMO

Anthropogenic activities increase the accumulation of heavy metals in the soil environment. Soil pollution significantly reduces environmental quality and affects the human health. In the present study soil samples were collected at different locations of Yelagiri Hills, Tamilnadu, India for heavy metal analysis. The samples were analyzed for twelve selected heavy metals (Mg, Al, K, Ca, Ti, Fe, V, Cr, Mn, Co, Ni and Zn) using energy dispersive X-ray fluorescence (EDXRF) spectroscopy. Heavy metals concentration in soil were investigated using enrichment factor (EF), geo-accumulation index (Igeo), contamination factor (CF) and pollution load index (PLI) to determine metal accumulation, distribution and its pollution status. Heavy metal toxicity risk was assessed using soil quality guidelines (SQGs) given by target and intervention values of Dutch soil standards. The concentration of Ni, Co, Zn, Cr, Mn, Fe, Ti, K, Al, Mg were mainly controlled by natural sources. Multivariate statistical methods such as correlation matrix, principal component analysis and cluster analysis were applied for the identification of heavy metal sources (anthropogenic/natural origin). Geo-statistical methods such as kirging identified hot spots of metal contamination in road areas influenced mainly by presence of natural rocks.


Assuntos
Metais Pesados/análise , Poluentes do Solo/análise , Espectrometria por Raios X/métodos , Análise por Conglomerados , Monitoramento Ambiental/métodos , Intoxicação por Metais Pesados , Humanos , Índia , Análise Multivariada , Intoxicação , Análise de Componente Principal , Solo/química , Análise Espacial
8.
Artigo em Inglês | MEDLINE | ID: mdl-24287055

RESUMO

Analytical investigations using Fourier Transform infrared spectroscopy (FT-IR), Powder X-ray Diffraction (PXRD), Thermal Analysis (TG-DTA), Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Fluorescence Spectrometry (EDXRF) were carried out on ancient pottery fragments from Kaveripakkam, in order to outline manufacturing skills, technology information, firing condition and temperature of potteries. The whole set of data showed the firing temperature in the range of 800-900°C. The analytical characterization of the potsherds, by different complimentary techniques has allowed to identifying the raw materials and technology applied by the ancient artisans.


Assuntos
Cerâmica/análise , Cerâmica/química , Análise Espectral/métodos , Análise Diferencial Térmica , História Antiga , Índia , Microscopia Eletrônica de Varredura , Minerais/análise , Pós , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Termogravimetria , Fatores de Tempo , Vibração , Difração de Raios X
9.
Artigo em Inglês | MEDLINE | ID: mdl-23892348

RESUMO

Analytical characterization of megalithic sarcophagi potsherds from Veeranam, Tiruvannamalai dist., Tamilnadu has been performed using Fourier transform infrared spectroscopy (FTIR), Powder X-ray diffraction (PXRD), Thermal analysis (TG-DTA), Scanning Electron Microscopy (SEM) coupled with an energy-dispersive X-ray spectrometer (EDX) and Energy dispersive X-ray fluorescence spectrometry (EDXRF). The EDXRF data of the potsherds were processed using multivariate statistical methods. Principal Component Analysis (PCA) and hierarchical cluster analysis allow us to identify grouping and structure in the data. The analytical results achieved in this study allowed us to estimate the firing temperature and manufacturing techniques. The methodological approach was successfully applied to the mineralogical, chemical and thermal characterization of the potsherds.


Assuntos
Silicatos de Alumínio/análise , Arqueologia , Argila , Análise por Conglomerados , Análise Diferencial Térmica , Índia , Microscopia Eletrônica de Varredura , Minerais/análise , Pós , Análise de Componente Principal , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Termogravimetria , Difração de Raios X
10.
Dis Markers ; 33(4): 207-13, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22960346

RESUMO

BACKGROUND: Obesity is considered as a strong risk factor of inflammatory periodontal tissue destruction. The purpose of this study is to determine presence of progranulin (PGRN) and high sensitivity C reactive protein (hs CRP) levels in serum and gingival crevicular fluid (GCF) in obese subjects with chronic periodontitis and to find an association, if any. MATERIAL AND METHODS: 40 subjects (20 males and 20 females) were selected based on their clinical parameters into four groups (10 subjects in each group): group 1 (healthy non obese), group 2 (healthy obese), group 3 (non obese with chronic periodontitis) and group 4 (obese with chronic periodontitis). Serum and GCF PGRN levels were estimated by enzyme linked immunosorbant assay (ELISA) and hs CRP levels were estimated by immunoturbidimetry method. RESULTS: The mean PGRN and hs CRP concentration both in serum and GCF were highest for group 4 followed by group 3, group 2 and least in Group 1. CONCLUSION: PGRN and hs CRP may be novel biomarkers of the chronic inflammatory response in obesity and chronic periodontitis.


Assuntos
Proteína C-Reativa/análise , Periodontite Crônica/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/análise , Obesidade/metabolismo , Adulto , Estudos de Casos e Controles , Periodontite Crônica/complicações , Periodontite Crônica/diagnóstico , Feminino , Líquido do Sulco Gengival/química , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/sangue , Masculino , Obesidade/sangue , Obesidade/complicações , Progranulinas
11.
Nucleic Acids Res ; 38(Web Server issue): W487-96, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20444870

RESUMO

Polyketide synthases (PKSs) catalyze biosynthesis of a diverse family of pharmaceutically important secondary metabolites. Bioinformatics analysis of sequence and structural features of PKS proteins plays a crucial role in discovery of new natural products by genome mining, as well as in design of novel secondary metabolites by biosynthetic engineering. The availability of the crystal structures of various PKS catalytic and docking domains, and mammalian fatty acid synthase module prompted us to develop SBSPKS software which consists of three major components. Model_3D_PKS can be used for modeling, visualization and analysis of 3D structure of individual PKS catalytic domains, dimeric structures for complete PKS modules and prediction of substrate specificity. Dock_Dom_Anal identifies the key interacting residue pairs in inter-subunit interfaces based on alignment of inter-polypeptide linker sequences to the docking domain structure. In case of modular PKS with multiple open reading frames (ORFs), it can predict the cognate order of substrate channeling based on combinatorial evaluation of all possible interface contacts. NRPS-PKS provides user friendly tools for identifying various catalytic domains in the sequence of a Type I PKS protein and comparing them with experimentally characterized PKS/NRPS clusters cataloged in the backend databases of SBSPKS. SBSPKS is available at http://www.nii.ac.in/sbspks.html.


Assuntos
Policetídeo Sintases/química , Software , Domínio Catalítico , Internet , Modelos Moleculares , Policetídeo Sintases/metabolismo , Análise de Sequência de Proteína , Especificidade por Substrato
12.
Environ Monit Assess ; 171(1-4): 411-24, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20058071

RESUMO

A significant variation in physicochemical properties of the Kalpakkam coastal waters, eastern part of India, was observed during the event of southwest to northeast monsoon transition. Increase in nitrate, total nitrogen, and silicate concentrations were noticed during post-transition period. Ammonia concentration was at peak during transition period as compared to pre- and post-transition periods. Hypo-saline condition (~23 psu) was observed during post-transition as the surface water salinity decreased by ~10 psu from the pre-transitional values. Turbidity, suspended particulate matter, phosphate and total phosphorous values decreased marginally, coinciding with northward to southward current reversal. A drastic decrease (eightfold) in chlorophyll-a concentration was observed in the coastal water during post-transition period.


Assuntos
Tempestades Ciclônicas , Água do Mar/química , Amônia/análise , Clorofila/análise , Análise por Conglomerados , Monitoramento Ambiental , Índia , Nitratos/análise , Nitrogênio/análise , Fósforo/análise , Análise de Componente Principal , Salinidade , Estações do Ano , Silicatos/análise
13.
Environ Monit Assess ; 164(1-4): 153-71, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-19404759

RESUMO

A study pertaining to the seasonal variation in physicochemical properties of the coastal waters was carried out at Kalpakkam coast for a period of 1 year (February 2006 to January 2007). It revealed that the coastal water was significantly influenced by freshwater input during North East (NE) monsoon and post-monsoon periods. Concentration of all the nutrients and dissolved oxygen (DO) was relatively high during the NE monsoon, whereas, salinity and chlorophyll-a (chl-a) were at their minimum level during this period. Phytoplankton production peak was observed in summer during which a typical marine condition prevailed. The present observed values of nitrate, phosphate, silicate, and turbidity are significantly high (five to ten times) compared to that of the pre-Tsunami period from this coast. Relatively low DO and chl-a concentration was noticed during the post-Tsunami period. A notable feature of this study is that though nutrient concentration in the coastal waters during post-Tsunami period has increased significantly, turbidity, the most single dominating factor, was found to adversely affect the phytoplankton production during post-Tsunami period as reflected by relatively low chl-a concentration. Thus, the post-Tsunami period may result in a change in coastal biodiversity pattern concomitant with change in coastal water quality.


Assuntos
Estações do Ano , Água do Mar/química , Índia
14.
Environ Monit Assess ; 163(1-4): 185-94, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19266296

RESUMO

Impact of thermal discharge from a coastal power station (Madras Atomic Power Station, southeast coast of India) on the spatial variability of Donax cuneatus abundance was assessed to determine the impact boundary. Totally, 20 sites were selected both on south and north side in increasing spatial scale from mixing zone, 12 locations were selected toward south side at a distance from 0 (near mixing point) to 2,000 m and eight location were selected toward north from the effluent mixing zone. Mean water temperature along the coast ranged from 29.1 +/-0.15 degrees C to 31.2 +/- 0.15 degrees C. Total organic carbon content in the sediment ranged from 0.27% to 0.70%. D. cuneatus population on the swash zone was ranged between 1.3 +/- 1.5 and 88.3 +/- 9.6 m(-2). Meager population of wedge clam was observed up to 100 m (S100) south from mixing point and abundance gradually increased in different spatial scale. Comparatively high abundance was observed from S400 and reached maximum at S1000 (64.0 +/- 3.6 m(-2)). Similar pattern was observed on north side too but less abundance was observed only up to 80 m (N80). Maximum abundance was observed at control location C3-N500 (88.3 +/- 9.6 m(-2)). Forty meters on either side of discharge point was highly impacted, 80 to 100 m toward plume flow (south) was moderately impacted, and 80 m north of mixing point also witnessed moderate impact. After 100 m (N100), north was not affected by effluents, whereas between 100 and 400 m, south was influenced slightly. Multivariate clustering pattern on the environmental variables of all sampling locations and population trend of D. cuneatus at those stations showed similarity. Present investigation unambiguously showed that the abundance pattern of D. cuneatus on the sandy beach of east coast of Kalpakkam is not governed by single major factor but due to the result of multiple interacting factors. The population size of the wedge clam with reference to the effect of power plant effluents and other features of habitats of the beach ecosystem are also discussed.


Assuntos
Bivalves , Centrais Nucleares , Animais , Dinâmica Populacional
15.
Environ Int ; 33(3): 346-56, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17196656

RESUMO

The paper presents the first document regarding concentration, distribution and possible sources of selected trace elements (Cu, Fe, Mn, Zn, Cr, Co, Ni, Pb, Al, B and Ba) in core sediments (<63 micro particle size) from the lower stretch of Hugli (Ganges) estuary, northeast coast of Bay of Bengal by ICP-AES and EDXRF to evaluate geochemical processes influencing their distribution and possible environmental consequences. The levels of elements showed a wide range of variations in different core depths, in upper and lower intertidal zones as well as among three sampling stations. The most interesting feature of the study is the downward increase of concentrations of majority of the elements reaching overall maximum values at a depth of 20-28 cm in upper littoral zone of the site located in the extreme downstream stretch of the estuary. Values of organic carbon showed very strong positive correlations with most of the elements as revealed by correlation matrix (r) values. The interelemental relationship revealed the identical behavior of element during its transport in the estuarine environment. The overall variation in concentration can be attributed to differential discharge of untreated effluents originating from industrial, agricultural, and aquacultural sources as well as from domestic sewage along with the fishing and boating activities. The resulting compositional dataset was tested by principal component analyses and cluster analyses. Pollution load index (PLI) and index of Geoaccumulation (Igeo) revealed overall low values but the enrichment factors (EFs) for Pb were typically high for all the stations. The mean concentrations of Zn and to some extent Cu exceeded the Effects Range-Low (ER-L) values in the majority of the cases indicating that there may be some ecotoxicological risk to organisms living in sediments. The concentration of the trace elements reported in this work is useful as baselines for comparison in future sediment quality studies.


Assuntos
Sedimentos Geológicos/análise , Metais/análise , Poluentes Químicos da Água/análise , Carbono/análise , Análise por Conglomerados , Monitoramento Ambiental , Índia , Análise de Componente Principal , Água do Mar , Clima Tropical
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