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1.
Indian J Sex Transm Dis AIDS ; 45(1): 31-33, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38989078

RESUMO

Introduction: The human immunodeficiency virus (HIV)/AIDS in India came into public view in 1986 with the detection of the first case of HIV in Chennai, Tamil Nadu, and the first AIDS case in Mumbai, Maharashtra in 1987. In acute phase response, iron distribution occurs in the liver and mononuclear phagocytic system. A high prevalence of elevated serum ferritin levels is reported in HIV infection and serum ferritin levels increase with the clinical worsening of infection and with decreasing CD4 lymphocyte counts. This study is designed to find the role of acute phase reactant serum ferritin in the progression of the disease of HIV which is complicated by opportunistic infections, by finding the correlation of serum ferritin with immunological stages of HIV. Materials and Methods: This cross-sectional study was conducted on 75 patients admitted to various wards of the Department of Medicine or attending medicine outdoor or ART Centre, Maharana Bhupal Government Hospital, RNT Medical College Udaipur. Serum ferritin, total iron binding capacity, and total serum iron were analyzed in Cobas® analyzer. CD4 cells are measured using the flow cytometry technique. The results were tabulated and subjected to statistical analysis. Results and Conclusion: There was a negative correlation among serum ferritin and CD4 cells with r = -0.195 which was statistically significant (P < 0.05). As the CD4 cell count decreased incidence of serum ferritin increased. Elevation of serum ferritin levels is associated with a low count of the CD4+ in HIV-diagnosed patients. In a patient diagnosed with HIV, elevated serum ferritin indicates underlying inflammatory pathology. Serum ferritin can be used as a guide to further evaluation of underlying disease in HIV patients.

2.
Opt Express ; 31(18): 29942-29953, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37710783

RESUMO

Light propagation has been studied in photonic crystal fibers (PCFs) doped with W212 ferroelectric liquid crystal (FLC) composites with titanium dioxide nanoparticles (TiO2 NPs) of low concentrations between 0.2 and 1 wt. % in the FLC matrix. Optical microscopy observations indicated a slight increase of transition temperature to the isotropic phase by ∼1-2°C compared to the undoped FLC sample, and the TiO2 admixture was found to decrease free ionic charge impurities in the FLC, thus improving its electro-optical parameters. The switching time measurements in the PLCFs clearly indicate that TiO2 NPs reduce switching times for low electric field intensity, even by 32% compared to the undoped PLCF.

3.
Bull Environ Contam Toxicol ; 108(3): 491-499, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33594450

RESUMO

The cells of Chlorella vulgaris exhibited NaCl (0-400 mM) induced decrease in the growth, protein, chlorophyll, carbohydrate and total organic carbon, whereas total lipid and proline content increased with rising level of NaCl. Addition of NaHCO3 (20 mM) exhibited antagonistic effect against the adverse effect of salinity on the growth, level of macromolecules except proline. The SEM-EDS analysis of NaCl treated cells exhibited morphological variations as well as reduced accumulation of Na and Cl due to the presence of NaHCO3. The results on chlorophyll fluorescence induction kinetics revealed NaCl induced decline in the photosynthetic performance and quantum yield, while non-photochemical quenching of chlorophyll was enhanced, particularly at lower concentrations of NaCl. Addition of NaHCO3 to NaCl treated cells exhibited further increase in the non-photochemical quenching values. Thus, these results demonstrated that adverse impact of NaCl on the C. vulgaris cells was significantly mitigated in the presence of bicarbonate.


Assuntos
Chlorella vulgaris , Microalgas , Bicarbonatos/metabolismo , Bicarbonatos/farmacologia , Chlorella vulgaris/metabolismo , Clorofila/metabolismo , Microalgas/metabolismo , Nutrientes , Fotossíntese , Salinidade
4.
Bull Environ Contam Toxicol ; 108(3): 389-395, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32974764

RESUMO

Plant species possess a huge potential in restoration of fly ash ecosystem. Litter deposition and its decomposition in the ash deposited sites are two important processes of the fly ash ecosystem. In order to identify the biological potential of a plant species to aid restoration of fly ash deposited sites, it is needed to assess leaf litter decomposition as well as nutrient release pattern. In the present investigation, we studied the leaf litter decomposition of the plant species (Leucaena leucocephala, Pithecellobium dolce and Prosopis juliflora) and mix plantation in the fly ash ecosystem. The litter bag experiment was conducted in the area of plantation on the fly ash deposited site during a period of 365 days. Percentage of C and N was higher in L. leucocephala > P. dolce >Mix Plantation > P. juliflora while C/N ratio was higher in P. juliflora >Mix Plantation > L. leucocephala > P. dolce. L. leucocephala and P. dolce showed relatively fast decomposition rates (k = 1.27, 1.17), respectively while mix plantation (k = 0.82) and P. juliflora (k = 0.73) exhibited relatively slower decomposition rates. Thus, we noted that the decomposition rate of L. leucocephala was greater than the other selected species. This shows that the species having faster decomposition rate and nutrient release could be a factual choice for rehabilitation of fly ash deposited sites.


Assuntos
Ecossistema , Fabaceae , Cinza de Carvão , Nitrogênio/análise , Folhas de Planta/química
5.
Bull Environ Contam Toxicol ; 108(3): 500-506, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32930810

RESUMO

Ubiquitous distribution, fast growth rate and manifold relevance has credited algae a potential bioresource in current state of affairs of environmental degradation. In the present study, green alga Chlorococcum sp. has been collected from waste water, isolated and cultured to assess their accumulation and toxicity responses at different As(III) concentration. Results revealed that Chlorococcum sp. treated with 10 µM As(III) showed a minimal reduction (21%) in chlorophyll concentration with high proline and carotenoids content indicating its adaptive tolerance potential against As(III). The EC50 of As(III) for inhibiting growth of the microalgae after 10 days of experiment was 9.4 µM. Further, Chlorococcum sp. accumulated 239.09 µg g- 1 dw As at the concentration of 10 µM of As(III) after 10 days of treatment. Concentration dependent accumulation pattern and antioxidant responses in Chlorococcum sp. could be a used as a potential bioindicator and bioremediator of As from waste water.


Assuntos
Microalgas , Bioacumulação , Biodegradação Ambiental , Microalgas/metabolismo , Águas Residuárias
6.
Int J Phytoremediation ; 24(8): 831-841, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34748446

RESUMO

The present study was conducted to assess the strain aptness, phycoremediation potential and lipid yield in microalgae Chloroccocum humicola and Oscillatoria sp. Results revealed that microalgae treated with different concentration of wastewater (25%, 50%, 75% and 100%) recovered nutrients (Nitrogen: 50.55-85.90%, Phosphorus: 69.98-93.72%) and removed heavy metals (24.17-88.10%) from wastewater. Microalgae C. humicola showed significant reduction in physico-chemical parameters of wastewater at 25% and 50% respectively with considerable increase in lipid production (1.61 folds) at 50% wastewater concentration. In order to counterbalance the wastewater induced toxicity, both microalgae exhibited stimulated antioxidants viz., proline (1.26-4.04 folds), ascorbic acid (1.01-9.21 folds), cysteine (1.44-4.92 folds), catalase (0.99-3.63 folds), superoxide dismutase (1.15-1.43 folds) and glutathione reductase (1.43-6.67 folds) at different wastewater concentrations. Further, Fourier transforms infrared spectroscopy spectral elucidation of Chloroccocum humicola at 50% reflected high lipid peak in the regions 3000-2800 cm-1 as compared to Oscillatoria sp. Thus, growth characteristics, biochemical responses and lipid yield presented the suitability of the Chloroccocum humicola to be used in phycoremedation, resource recovery as well as lipid production, which may be further utilized as potent feedstock for third generation energy demand.


Assuntos
Metais Pesados , Microalgas , Oscillatoria , Biodegradação Ambiental , Biocombustíveis , Biomassa , Lipídeos , Nitrogênio , Superóxido Dismutase , Águas Residuárias/química
7.
Mar Pollut Bull ; 172: 112883, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34455346

RESUMO

We studied the relationship between organic carbon in sediments (%Corg), bottom water dissolved oxygen and living benthic foraminifera in a marginal marine upwelling setting from the southeastern Arabian Sea to develop proxy indicator for marine productivity as well as oxygen deficient zones. The surface sediments from 43 stations covering a depth range of 25 to 2980 m were used. The relationship between living benthic foraminifera and ambient environmental parameters (seawater temperature, salinity, dissolved oxygen, organic carbon and Corg/TN and depth) was assessed by multivariate analysis. A majority of the living benthic foraminifera were significantly affected by several ambient parameters. We report that the living benthic foraminiferal assemblage comprising of Epistominella umbonifera, Uvigerina auberiana, Reophax longicollis and Osangularia bengalensis is significantly affected only by %Corg in the sediment. Additionally, we also found that the assemblage including Bolivina obscuranta, Bulimina arabiensis, Bulimina pseudoaffinis and Cancris penangensis is significantly affected only by the bottom water dissolved oxygen. The living benthic foraminifera assemblages can be used to reconstruct marine productivity and dissolved oxygen concentration in the past.


Assuntos
Foraminíferos , Monitoramento Ambiental , Sedimentos Geológicos , Oxigênio/análise , Água do Mar
8.
Mater Today Proc ; 46: 11267-11273, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33816130

RESUMO

The counter of COVID-19 seems nerve-wracking right now and the cumulative cases are increasing with an unstoppable speed each second. This outbreak situation brings an anxious time for researchers and scientists, as the pressure is keep mounting on them each second to find any optimal solution of this situation. This work dissect one important section which affected most by this novel corona virus, i.e. world health index. In simple terms, how COVID-19 attack on WHI's top vs mediocre nations. This paper outlines how the countries which has lowest ranking in World Health Index, either escape or least affected from the disease initially compare to the countries which top the WHI affect most and after a period how higher ranking countries in WHI overcome significantly and quickly than lower ranks countries. This work consolidates the data majorly from COVID-19 worldometer and WHI data as a primary source. Moreover, conduct a statistical data analysis to determine the key factors behind larger affected COVID-19 nations and factors which helps those nations who overcome from COVID-19 comparatively. Finally, this work provides prediction for undiscover areas, so that the comparatively saved nations from COVID-19 can work on those vital considerations and avoid severe attack of COVID-19.

9.
Arch Microbiol ; 203(5): 2199-2209, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33625538

RESUMO

A halotolerant bacterial strain isolated and identified as Bacillus gibsonii was used for extracellular lipase production. The bacterial strain was able to grow up to 1200 mM salt concentration and showed maximum growth at 600 mM NaCl concentration. The present study includes production of extracellular lipase enzyme and characterization of partially purified lipase with respect to its kinetic and thermodynamic behaviour. Maximum lipase activity was observed at 60 °C under alkaline pH (9.0) condition. The kinetic parameters such as Vmax, Km and Kcat were calculated as 158.73 U/mL, 0.539 mM and 483.93 min-1 at 60 °C, respectively, suggested thermostable nature of the enzyme. The thermal inactivation energy [Ea(d)] was calculated as 66.98 kJ/mol. The values of Gibb's free energy (86.31 kJ/mol), enthalpy (64.26 kJ/mol) and entropy (- 66.21 × 10-3 kJ/mol/K) for the enzyme inactivation obtained at 60 °C corroborated the assumption that 60 °C was the optimum temperature. Further, the deactivation rate constant (kd) values calculated at 60 °C and 80 °C were found to be 0.0907 and 0.182 min-1, respectively, which suggested that enzyme was more stable at 60 °C and it was partly inactivated at 80 °C.


Assuntos
Bacillus/enzimologia , Bacillus/metabolismo , Lipase/metabolismo , Termodinâmica , Bacillus/genética , Estabilidade Enzimática , Temperatura Alta , Concentração de Íons de Hidrogênio , Cinética , Temperatura
10.
J Therm Biol ; 95: 102792, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33454033

RESUMO

Soaring temperatures cause deaths in large numbers in various parts of India. The number of deaths vary with region and are influenced by the demographics and socioeconomic characteristics of the region. This study tried to estimate the number of deaths associated with exposure to heat in the different states of India. Secondary data was used, which was collected from the website data.gov.in, an Open Government Data (OGD) Platform of the Indian government. Descriptive statistics were applied using Microsoft Excel-10. It was found that there 3014 men died from heat-related causes in 2001-05, which increased to 5157 in the period 2011-15. For women the number of deaths in the corresponding periods were 849 and 1254 respectively. Deaths caused by heatwaves were found to be higher than those resulting from avalanches, exposure to cold, cyclone, tornado, starvation due to natural calamity, earthquake, epidemic, flood, landslide, torrential rain and forest fire. The study revealed that there are regional variations in the number deaths due to heatstroke. From the perspective of disaster preparedness, it is important to note that deaths from heat strokes occur every year. With rising temperatures, the numbers are likely to increase. The findings of the study highlight this concern. Therefore, there is a need for targeted region-specific interventions for reducing the number of deaths due to heatwaves.


Assuntos
Golpe de Calor/epidemiologia , Adolescente , Adulto , Fatores Etários , Idoso , Feminino , Golpe de Calor/mortalidade , Temperatura Alta , Humanos , Índia , Raios Infravermelhos , Masculino , Pessoa de Meia-Idade , Mortalidade/tendências , Estações do Ano , Fatores Sexuais , Fatores Socioeconômicos
11.
Biotechnol Rep (Amst) ; 27: e00484, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32637344

RESUMO

Plants, being sessile, are exposed to an array of abiotic and biotic stresses. To adapt towards the changing environments, plants have evolved mechanisms that help in perceiving stress signals wherein phytohormones play a critical role. They have the ability to network enabling them to mediate defense responses. These endogenous signals, functioning at low doses are a part of all the developmental stages of the plant. Phytohormones possess specific functions as they interact with each other positively or negatively through cross-talks. In the present study, variations in the amount of phytohormones produced during biotic stress caused due to Magnoporthe grisea infection was studied through targeted metabolomics in both primed and control finger millet plants. Histochemical studies revealed callose deposition at the site of pathogen entry in the primed plants indicating its role during plant defense. The knowledge on the genetic makeup during infection was obtained by quantification of MAP kinase kinases 1 and 2 (MKK1/2) and lipoxygenase (LOX) genes, wherein the expression levels were high in the primed plants at 6 hours post-inoculation (hpi) compared to mock-control. Studies indicate the pivotal role of mitogen-activated protein kinase (MAPK or MAP kinases) during defense signalling. It is the first report to be studied on MAPK role in finger millet-blast disease response. Temporal accumulation of LOX enzyme along with its activity was also investigated due to its significant role during jasmonate synthesis in the plant cells. Results indicated its highest activity at 12 hpi. This is the first report on the variation in phytohormone levels in fingermillet - M. grisea pathosystem upon priming which were substantiated through salicylic acid (SA) pathway.

12.
Nat Commun ; 11(1): 2210, 2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-32372005

RESUMO

Symmetry breaking and the emergence of self-organized patterns is the hallmark of complexity. Here, we demonstrate that a sessile drop, containing titania powder particles with negligible self-propulsion, exhibits a transition to collective motion leading to self-organized flow patterns. This phenomenology emerges through a novel mechanism involving the interplay between the chemical activity of the photocatalytic particles, which induces Marangoni stresses at the liquid-liquid interface, and the geometrical confinement provided by the drop. The response of the interface to the chemical activity of the particles is the source of a significantly amplified hydrodynamic flow within the drop, which moves the particles. Furthermore, in ensembles of such active drops long-ranged ordering of the flow patterns within the drops is observed. We show that the ordering is dictated by a chemical communication between drops, i.e., an alignment of the flow patterns is induced by the gradients of the chemicals emanating from the active particles, rather than by hydrodynamic interactions.

13.
Environ Geochem Health ; 42(12): 4101-4111, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32060865

RESUMO

The presence of heavy metal in soil and water resources has serious impact on human health. The study was designed to examine the phytoremediation ability of plant species that are growing naturally on the Zn-contaminated site. For the study, six plant species and their rhizospheric soil as well as non-rhizospheric soil samples were collected from different parts of the industrial sites for chemical and biological characterization. Visual observations and highest importance value index (IVI) through biodiversity study revealed potential plants as effective ecological tools for the restoration of the contaminated site. Among the plants, almost all were the most efficient in accumulating Fe, Mn, Cu and Zn in its shoots and roots, while Cynodon dactylon, Chloris virgata and Desmostachya bipinnata were found to be stabilizing Cr, Pb and Cd (bioconcentration factor in root = 7.95, 6.28 and 1.98 as well as translocation factor = 0.48, 0.46 and 0.78), respectively. Thus, the results of this study showed that the naturally growing plant species have phytoremediation potential to remediate the electroplating wastewater-contaminated site. These plant species are successful phytoremediators with their efficient metal stabilizing and well-evolved tolerance to heavy metal toxicity.


Assuntos
Galvanoplastia , Metais Pesados/metabolismo , Plantas/metabolismo , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/metabolismo , Biodegradação Ambiental , Biodiversidade , Metais Pesados/análise , Raízes de Plantas/classificação , Raízes de Plantas/metabolismo , Plantas/classificação , Rizosfera , Poluentes do Solo/análise , Poluentes do Solo/metabolismo , Poluentes Químicos da Água/análise
14.
Mater Sci Eng C Mater Biol Appl ; 105: 110119, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31546342

RESUMO

A series of CuII, CoII, ZnII and NiII, complexes of 34,74-dimethyl-12,15,52,55-tetrahydro-2,4,6,8-tetraaza-1,5(2,5)-difurana-3,7(1,2)-dibenzenacyclooctaphane based ligand have been synthesized by template methodology. Characterization of the synthesized complexes has been carried out with the help of various physicochemical and spectroscopic techniques like Infra-Red, ESI-MS, ESR, UV-visible, CHN (elemental analyses), molar conductance, magnetic moment and NMR. Antimicrobial efficacy of the newly designed macrocyclic complexes has performed by the assistance of agar well diffusion method. In-vitro hemolytic and DNA binding studies were also performed in order to analyze or interpret the mode and binding efficiencies as well as the % hemolysis exhibited by the complexes. DFT/TD-DFT studies were carried out in order to elucidate the better insight into the structural parameters. Energy minimization and quantum chemical parameters were calculated using Gaussian09W program.


Assuntos
Anti-Infecciosos/síntese química , Anti-Infecciosos/farmacologia , Compostos Macrocíclicos/síntese química , Compostos Macrocíclicos/farmacologia , Bases de Schiff/síntese química , Bases de Schiff/farmacologia , Animais , Anti-Infecciosos/química , DNA/metabolismo , Espectroscopia de Ressonância de Spin Eletrônica , Peixes , Hemólise/efeitos dos fármacos , Compostos Macrocíclicos/química , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Conformação Molecular , Bases de Schiff/química , Espectrofotometria Infravermelho
15.
Phys Chem Chem Phys ; 21(34): 18686-18698, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31423509

RESUMO

We explore the molecular nature of doping in organic semiconductors (OSCs) by employing a liquid crystalline organic semiconductor based on phenyl naphthalene as a model. The mesophase nature of composites that include a charge transfer complex (CTC) between the OSC (8-PNP-O12) and an electron acceptor (F4TCNQ) has been investigated by means of differential scanning calorimetry, polarized optical microscopy and X-ray scattering. Optical and vibrational spectroscopies allow us to explore the characteristics and the amount of charge transfer in the CTC and expose some properties that appear only in the complexed state. We have found this system to exhibit partial charge transfer, which manifests itself in all the phase states of the host 8-PNP-O12, as well as in solution. Due to the lowering of molecular symmetry as a result of the charge transfer, one of the previously IR-only vibrational bands of the nitrile group is found to be now active in the Raman spectrum. We have also made an attempt to further investigate the influence of dopant introduction on the bulk hole mobility of 8-PNP-O12. It is found that the presence of the CTC promotes the hole transport in the Smectic B mesophase, however it seems to have a somewhat negative influence in the less ordered smectic A mesophase. This work aims to establish the link between the inevitable change of molecular geometry that occurs on charge transfer with the results obtained by spectroscopic techniques and electronic charge carrier mobility measurements.

16.
Ecotoxicol Environ Saf ; 176: 27-33, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-30909001

RESUMO

Adsorption behavior of Mentha Plant Ash (MPA) in removal of Cr(VI) from aqueous solution was analyzed as a function of different pH (3.0-8.0), different concentration of Cr(VI) (10-50 mg L-1), contact time (0-90 min) and doses of adsorbent (0.1-0.5 g/100 mL). Adsorption of Cr(VI) onto MPA was found to be dependent on pH condition of the solution and showed maximum removal of Cr(VI) at pH 3.0. The study of adsorption kinetics on Cr(VI) removal by MPA showed that pseudo-second order kinetic model was more suitable to describe the Cr(VI) removal by adsorption onto MPA. Results on Cyclic Voltammetry study of MPA treated with Cr(VI) solution revealed the reduction of Cr(VI) to Cr(III) and Cr(II) by MPA particles through multi-step electron transfer reactions. A combined effect of adsorption and reduction properties of MPA was particularly responsible for removal and transformation of Cr(VI). These attributes of MPA were contributed by many active Cr(VI) binding and electron donating ligands present on the MPA surface as evident from FTIR and XPS analysis of MPA.


Assuntos
Cromo/análise , Mentha piperita/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Água/química , Adsorção , Cromo/química , Concentração de Íons de Hidrogênio , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/química
17.
Ecotoxicol Environ Saf ; 174: 706-713, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-30878807

RESUMO

Microalga Scenedesmus vacuolatus exhibited maximum growth, protein and carbohydrate contents at 10.0 mM concentration of nitrate, 1.0 mM of glutamate nitrogen and at C/N ratio (12 mM acetate+10 mM nitrate). However, these cell constituents showed the highest values in the C+N grown cells, but the lipid content was found to be the highest glutamate grown cells. FTIR analysis of Lipid/Carbohydrate and Lipid/Protein ratio and flow cytometric analysis of neutral lipids revealed higher lipid content in the glutamate grown cells than in the nitrogen starved, nitrate and C+N grown cells. The nitrate reductase activity was the highest in the C+ N grown cells and the lowest activity was found in the glutamate grown cells. A corollary of these results suggested that suppression of nitrogen assimilatory system, whether by glutamate or by nitrogen deprivation, was the most suitable physiological condition for enhanced lipid synthesis and biofuel production in microalgal cells.


Assuntos
Biocombustíveis , Lipídeos/biossíntese , Microalgas/metabolismo , Nitrogênio/metabolismo , Scenedesmus/metabolismo , Biocombustíveis/análise , Biomassa , Carbono/metabolismo , Meios de Cultura/química , Lipídeos/análise , Microalgas/crescimento & desenvolvimento , Nitrato Redutase/metabolismo , Nitratos/metabolismo , Nitrogênio/deficiência , Scenedesmus/crescimento & desenvolvimento
18.
RSC Adv ; 9(36): 20536-20548, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35686289

RESUMO

The present study reports the impact of thermal annealing on the structural, optical and magnetic properties of WO3 nanostructures, synthesized using an acid precipitation method by, employing various spectroscopic and magnetic measurements. The X-ray diffraction and Raman measurements confirmed the orthorhombic structure of as dried WO3·H2O and monoclinic structure of WO3 nanopowders annealed at or above 500 °C. The morphological characterization shows the formation of different microstructures like nanosheets, nanoplatelets and nanocuboids in the micro-scale with the variation of annealing temperatures. The optical band gap has been calculated using the Kubelka-Munk function. The room temperature photoluminescence (PL) spectra recorded at different excitation wavelengths show intense near ultraviolet (NUV) emission which might be due to the presence of localized states associated with oxygen vacancies, and the surface states in the conduction band. The emissions in visible region correspond to the structural defects such as oxygen vacancies present within the band gap and band to band transitions. The spectral chromaticity colour coordinates indicate that the light emitted from the prepared samples shows shift from violet to red region with the change of excitation wavelength. Magnetic measurements show decrease in room temperature ferromagnetism (FM) with annealing temperature. The X-ray absorption spectroscopy (XAS) measurements at O K-edge show the significant change in the W-O hybridizations. The decrease in PL intensity and ferromagnetic ordering with increase in annealing temperatures are directly correlated with the filling up of oxygen vacancies in the samples. The oxygen vacancies based F-Center exchange model is discussed to understand the origin of FM in WO3 nanostructures.

19.
Bioresour Technol ; 270: 489-497, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30245319

RESUMO

In the present study, microalgae Chlorococcum humicola and Chlorella vulgaris were grown in different concentrations of NaCl (25-1000 mM) to elucidate its impact on morphology, lipid synthesis, minerals status and antioxidative responses. Scanning Electron microscopy showed distorted cell morphology and increased cell size by 33.52% (C. humicola) and 27.79% (C. vulgaris) at 100 mM NaCl. Energy Dispersive Spectroscopy data revealed reduction in mineral contents (C, S, Fe, Mg, Si, Mn and Zn) by 14-54% in both algae. Further, C. humicola was found to have high lipid content than C. vulgaris under NaCl regime. The activities of superoxide dismutase, catalase and glutathione reductase were increased by 2.5-5 folds in both algae as compared to control. The increased level of ascorbate, cysteine and proline in both algae indicated tolerance against salinity. Thus, C. humicola and C. vulgaris may exhibit dual benefits viz., high lipid production and reclamation of sodic soil.


Assuntos
Antioxidantes/metabolismo , Chlorella vulgaris/metabolismo , Clorófitas/metabolismo , Lipídeos/biossíntese , Nutrientes/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Cloreto de Sódio/farmacologia , Catalase/metabolismo , Chlorella vulgaris/efeitos dos fármacos , Clorófitas/efeitos dos fármacos , Glutationa Redutase/metabolismo , Superóxido Dismutase/metabolismo
20.
Chemosphere ; 206: 122-131, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29738902

RESUMO

This study aimed to investigate the effects of potentially toxic elements on biochemical parameters in wheat (Triticum aestivum L.) and mustard (Brassica juncea L.) plants growing at distillery and tannery wastewater contaminated sites. The analysis of plants showed the highest accumulation of Fe (361 mg kg-1 in wheat root and 359 mg kg-1 in mustard leaves) followed by Zn, Cr and Mn in leaf>shoot>root. Further, the Chl-a, b, and carotenoids content was also found high in plant samples. Results also showed that photosynthetic content in wheat and mustard growing at tannery wastewater contaminated sites was Chl-a 3.92, 4.53 (mg g_1 fw), Chl-b 2.39, 1.29 (mg g_1 fw) and carotenoids 0.28, 0.32 (mg g_1 fw), respectively. Whereas, photosynthetic content in these plants with distillery waste was as Chl-a 3.43, 4.88 (mg g_1 fw), Chl-b 1.12, 2.05 (mg g_1 fw) and carotenoids 0.24, 0.29 (mg g_1 fw), respectively. In addition, the activity of plant enzymes such as SOD, APx, GPX, MDA, H2O2, and CAT was also higher in selected plants in comparison to control plants. Moreover, the high bioconcentration factor of Zn > 1 (1.29) and translocation factor >10 (10.31) of Cr in tannery wastewater affected mustard plants. This study concluded that industrial wastewaters are the primary sources of metal accumulation in agricultural crops and thus, it should not be discharged into the environment before its proper treatment. Hence, the continuous monitoring of sludge/soil, agricultural plants and water quality are imperative for the impediment of possible health hazards to animal and human beings.


Assuntos
Metais Pesados/química , Triticum/química , Águas Residuárias/química , Humanos
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