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1.
J Chem Phys ; 160(19)2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38767258

RESUMEN

In this work, the electromigration dispersion (EMD) due to the charged electrolytes in microchannels is considered without using the thin electrical double layer assumption. The electrokinetic flow and transport of ions are actuated within a rectangular micro-/nanochannel having a negative surface charge density under the influence of an external electric field. Due to the local variation of the conductivity and the nonvalidity of the electroneutrality condition, the local electric field varies as a function of the solute concentration, wall surface charge density, valency, and Debye layer length. The resulting electrokinetic flow due to the external electric field drives the fluid along with the charged species, where the Taylor-Aris dispersion separates the solutes into their different constituents. The local concentration dependence of the electric field leads to the formation of concentration profiles that are slightly asymmetric with respect to the standard Gaussian distribution. Including a finite Debye layer thickness has an effect on the advection of the species as well as the diffusion of the species. It is found that in cases where Debye layers are thicker, the species advects faster within the microchannel. This might give valuable insights into the nature of the EMD. Our model aims to predict the evolution of ionic concentration at all positions within the channel. A study of the higher-order statistics in skewness and kurtosis has also been conducted to obtain a better understanding of the idealized model consisting of a buffer solution.

2.
Environ Geochem Health ; 46(2): 65, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38321197

RESUMEN

Rice-based integrated farming system improves the productivity and profitability by recycling resources efficiently. In the sub-humid tropics, rice production without sufficient nutrient replenishment often leads to soil health and fertility degradation. There has been very limited research on soil health and fertility after adopting a multi-enterprising rice-based integrated farming system (IFS), notably in the rice-fish-livestock and agroforestry system, when compared to a conventional farming system (CS). Therefore, the present study analyzed the dynamics of soil properties, soil bacterial community structure and their possible interaction mechanisms, as well as their effect on regulating soil quality and production in IFS, IFSw (water stagnant area of IFS) and CS. The results indicated that soil nutrient dynamics, bacterial diversity indices (Shannon index, Simpson index, Chao 1, ACE and Fisher index) and system productivity were higher in IFSw and IFS compared to CS. Moreover, relative operational taxonomic units of dominant bacterial genera (Chloroflexi, Acidobacteria, Verrucomicrobia, Planctomycetes, Cyanobacteria, Crenarchaeota and Gemmatimonadetes) were also higher in IFSw and IFS compared to CS. Mean soil quality index (SQI) was highest in IFSw (0.780 ± 0.201) followed by IFS (0.770 ± 0.080) and CS (0.595 ± 0.244). Moreover, rice equivalent yields (REY) and rice yields were well correlated with the higher levels of soil biological indices (SQIBiol) in IFS. Overall, our results revealed that rice-based IFS improved the soil health and fertility and ensuing crop productivity through positive interaction with soil bacterial communities and nutrient stoichiometry leading to agroecosystem sustainability.


Asunto(s)
Oryza , Suelo , Suelo/química , Clima Tropical , Agricultura/métodos , Bacterias , Microbiología del Suelo
3.
Environ Geochem Health ; 45(11): 7979-7997, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37515727

RESUMEN

Nutrient management in resource conservation practices influence the structural and functional microbial diversities and thereby affect biological processes and biochemical properties in soil. We studied the long-term effects of resource conservation technologies on functional microbial diversity and their interactions with soil biochemical properties and enzymatic activities in tropical rice-green gram cropping system. The experiment includes seven treatments viz., conventional practice (CC), brown manuring (BM), green manuring (GM), wet direct drum sowing, zero tillage, green manuring-customized leaf colour chart based-N application (GM-CLCC-N) and biochar (BC) application. The result of the present study revealed that microbial biomass nitrogen (N), carbon (C) and phosphorus (P) in GM practice were increased by 23.3, 37.7 and 35.1%, respectively than CC. GM, BM and GM-CLCC-N treatments provide higher yields than conventional practice. The average well color development value, Shannon index and McIntosh index were significantly higher by 26.6%, 86.9% and 29.2% in GM as compared to control treatment. So, from this study we can conclude that resource conservation practices like GM, GM-CLCC N and BM in combination with chemical fertilizers provide easily decomposable carbon source to support the microbial growth. Moreover, dominance of microbial activity in biomass amended treatments (GM, GM-CLCC N and BM) indicated that these treatments could supply good amount of labile C sources on real time basis for microbial growth that may protect the stable C fraction in soil, hence could support higher yield and soil organic carbon build-up in long run under rice-green gram soil.


Asunto(s)
Oryza , Suelo , Suelo/química , Carbono/análisis , Biomarcadores Ambientales , Indicadores de Calidad de la Atención de Salud , Agricultura/métodos , Fertilizantes , Nitrógeno/análisis
4.
World J Microbiol Biotechnol ; 38(10): 168, 2022 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-35877011

RESUMEN

NrfA is the molecular marker for dissimilatory nitrate reduction to ammonium (DNRA) activity, catalysing cytochrome c nitrite reductase enzyme. However, the limited study has been made so far to understand the structural homology modeling of NrfA protein in DNRA bacteria. Therefore, three model DNRA bacteria (Escherechia coli, Wolinella succinogenes and Shewanella oneidensis) were chosen in this study for in-silico protein modeling of NrfA which roughly consists of similar length of amino acids and molecular weight and they belong to two contrasting taxonomic families (γ-proteobacteria with nrfABCDEFG and ε-proteobacteria with nrfHAIJ operon). Multiple bioinformatic tools were used to examine the primary, secondary, and tertiary structure of NrfA protein using three distinct homology modeling pipelines viz., Phyre2, Swiss model and Modeller. The results indicated that NrfA protein in E. coli, W. succinogenes and S. oneidensis was mostly periplasmic and hydrophilic. Four conserved Cys-X1-X2-Cys-His motifs, one Cys-X1-X2-Cys-Lys haem-binding motif and Ca ligand were also identified in NrfA protein irrespective of three model bacteria. Moreover, 11 identical conserved amino acids sequence was observed for the first time between serine and proline in NrfA protein. Secondary structure of NrfA revealed that α-helices were observed in 77.9%, 73.4%, and 77.4% in E. coli, W. succinogenes and S. oneidensis, respectively. Ramachandran plot showed that number of residue in favored region in E. coli, W. succinogenes and S. oneidensis was 97.03%, 97.01% and 97.25%, respectively. Our findings also revealed that among three pipelines, Modeller was considered the best in-silico tool for prediction of NrfA protein. Overall, significant findings of this study may aid in the identification of future unexplored DNRA bacteria containing cytochrome c nitrite reductase. The NrfA system, which is linked to respiratory nitrite ammonification, provides an analogous target for monitoring less studied N-retention processes, particularly in agricultural ecosystems. Furthermore, one of the challenging research tasks for the future is to determine how the NrfA protein responds to redox status in the microbial cells.


Asunto(s)
Compuestos de Amonio , Nitratos , Aminoácidos , Bacterias , Citocromos a1 , Citocromos c1 , Ecosistema , Escherichia coli/genética , Humanos , Nitrato Reductasas , Nitrito Reductasas/genética , Ciclo del Nitrógeno
5.
Ecotoxicol Environ Saf ; 189: 110019, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31816497

RESUMEN

Bispyribac sodium is frequently used herbicide in the rice field. Though, it has been targeted to kill rice weeds, but its non-target effect on soil microbes in paddy soil was largely unknown. Therefore, in the present study, an attempt was made to assess the non-target effect of bispyribac sodium on alteration of functional variation of soil microbial community and their correlation with microbial biomass carbon (MBC) and soil enzymes. A microcosm experiment set up was made comprising three treatments viz., control (CON) (without application of bispyribac sodium), recommended dose of bispyribac sodium (35 g ha-1) (BS), and double the dose of BS (70 g ha-1) (DBS). Results indicated that the MBC and soil enzyme activities (dehydrogenase, alkaline phosphatase and urease) in BS and DBS-treated soil were significantly (p < 0.05) declined from 1st to 30th day after application as compared to CON. Counts of heterotrophic bacteria, actinomycetes and fungal population were also decreased in BS and DBS-treated soil. The average well color development (AWCD) values derived from Biolog®ecoplates followed the order of DBS ˂ BS ˂ CON. Shannon index value was high (p ≤ 0.05) in CON compared to soil-treated with BS and DBS. Principal component analysis (PCA) showed a clear distinction of the cluster of treatments between CON, BS and DBS. Biplot analysis and heatmap suggested that carboxylic compounds and amino acids showed positive response towards BS-treated soil, whereas phenolic compounds had positive correlation with DBS-treated soil. PCA analysis indicated that oligotrophs was rich in BS-treated paddy soil, whereas copiotrophs and asymbiotic nitrogen fixers were richer in DBS treatment. Overall, the present study revealed that application of recommended dose of BS and its double dose alter the soil microbial population, enzyme activities and functional microbial diversity in paddy soil.


Asunto(s)
Benzoatos/toxicidad , Herbicidas/toxicidad , Microbiota/efectos de los fármacos , Pirimidinas/toxicidad , Microbiología del Suelo , Contaminantes del Suelo/toxicidad , Bacterias/clasificación , Bacterias/efectos de los fármacos , Bacterias/metabolismo , Benzoatos/análisis , Biomasa , Hongos/clasificación , Hongos/efectos de los fármacos , Hongos/metabolismo , Herbicidas/análisis , Oryza/crecimiento & desarrollo , Pirimidinas/análisis , Suelo/química , Contaminantes del Suelo/análisis
7.
Int J Biometeorol ; 63(3): 337-349, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30680629

RESUMEN

Photosynthetically active radiation (PAR) is one of the most important environmental factors that determine the productivity and grain quality of the crops. Continuous rainy days or cloudy weather throughout crop growth especially at critical stages often resulted in great loss of grain quality and yield in rice. Low light stress has rigorously constrained the rice production in various rice-growing regions, especially in Southeast Asia. Method and time of planting are the major management factors contributing to the higher yield potential of rice by influencing light harvesting and use efficiency. Present study was executed consecutively for 5 years (kharif seasons of 2012-2016) to determine whether planting time improves the radiation absorption and use efficiency in different duration rice cultivars. We evaluated the difference in plant growth and development leading to yield formation under different planting time which related to radiation incidence and interception. The results of the study revealed that PAR interception depends on morphological characters of cultivars and also with agronomic management such as transplanting time and method. Long duration cultivar intercepted more PAR but interception decreased due to late planting (3rd week of July), whereas short duration cultivars (Naveen) when planted earlier (1st week of June) could not effectively utilize intercepted PAR constraining the biomass accumulation and yield formation. Effect of planting density and crop architecture on PAR absorption was apparent among establishment methods as light interception at crop canopy was highest in the system of rice intensification and lowest in that of wet direct seeding. In general, Pooja as a long duration cultivar intercepted more PAR per day but when compared on same date of planting, the comparative absorption of radiation was 30.6% higher in Naveen. The lower yields in the wet season are attributed mostly to reduction in grain number per panicle or per unit land area, which is a consequence of high spikelet sterility. Grain yield of rice planted in July third week was reduced by 3.8, 12.3, and 6.9% over June first and third week and July first week, respectively, mainly due to spikelet sterility (26%) and lower grains per panicle (18%). Our results indicated that agronomic management like optimum time of sowing, cultivar duration, and establishment methods should be followed for yield improvement in tropical lowlands where light intensity is limiting due to prevailing weather situations.


Asunto(s)
Agricultura/métodos , Oryza/crecimiento & desarrollo , Luz Solar , Hojas de la Planta/crecimiento & desarrollo , Estaciones del Año , Temperatura
8.
Environ Monit Assess ; 191(2): 98, 2019 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-30675638

RESUMEN

Land use and land cover (LULC) change have considerable influence on ecosystem services. Assessing change in ecosystem services due to LULC change at different spatial and temporal scales will help to identify suitable management practices for sustaining ecosystem productivity and maintaining the ecological balance. The objective of this study was to investigate variations in ecosystem services in response to LULC change over 27 years in four agro-climatic zones (ACZ) of eastern India using satellite imagery for the year 1989, 1996, 2005, 2011 (Landsat TM) and 2016 (Landsat 8 OLI). The satellite images were classified into six LULC classes, agriculture land, forest, waterbody, wasteland, built-up, and mining area. During the study period (1989 to 2016), forest cover reduced by 5.2%, 13.7%, and 3.6% in Sambalpur, Keonjhar, and Kandhamal districts of Odisha, respectively. In Balasore, agricultural land reduced by 17.2% due to its conversion to built-up land. The value of ecosystem services per unit area followed the order of waterbodies > agricultural land > forests. A different set of indicators, e.g., by explicitly including diversity, could change the rank between these land uses, so the temporal trends within a land use are more important than the absolute values. Total ecosystem services increased by US$ 1296.4 × 105 (50.74%), US$ 1100.7 × 105 (98.52%), US$ 1867 × 105 (61.64%), and US$ 1242.6 × 105 (46.13%) for Sambalpur, Balasore, Kandhamal, and Keonjhar, respectively.


Asunto(s)
Cambio Climático , Conservación de los Recursos Naturales/métodos , Monitoreo del Ambiente/métodos , Agricultura/métodos , Ecosistema , Bosques , India , Minería , Imágenes Satelitales/métodos
9.
Int J Phytoremediation ; 20(7): 682-691, 2018 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-29723050

RESUMEN

Bioremediation of Cr (VI), Fe, and other heavy metals (HMs) through plant-microbes interaction is one of the efficient strategies due to its high efficiency, low cost, and ecofriendly nature. The aim of the study was to isolate, characterize, and assess the potential of rhizospheric bacteria to enhance growth and metal accumulation by the chromium hyperaccumulator Vetiveria zizanoides. The bacterial strain isolated from mine tailings was identified to be Bacillus cereus (T1B3) strain exhibited plant growth-promoting traits including, 1-aminocyclopropane-1-carboxylate deaminase, indole acetic acid, and siderophores production, nitrogen fixation, and P solubilization. Removal capacity (mg L-1) of T1B3 strain was 82% for Cr+6 (100), 92% for Fe (100), 67% for Mn(50), 36% for Zn (50), 31% for Cd (30), 25% for Cu (30), and 43% for Ni (50) during the active growth cycle in HM-amended, extract medium. Results indicate that inoculating the native V. zizanioides with T1B3 strain improves its phytoremediation efficiency of HMs. The mineralogical characteristics of chromite ore tailings and soil were also confirmed by X-ray diffraction, Fourier Transform Infrared, scanning electron microscope-energy dispersive spectroscopy analysis.


Asunto(s)
Chrysopogon , Metales Pesados/análisis , Contaminantes del Suelo/análisis , Bacillus cereus , Biodegradación Ambiental
11.
Ecotoxicol Environ Saf ; 114: 257-62, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24836933

RESUMEN

Fly ash (FA), a byproduct of coal combustion in thermal power plants, has been considered as a problematic solid waste and its safe disposal is a cause of concern. Several studies proposed that FA can be used as a soil additive; however its effect on microbial response, soil enzymatic activities and heavy metal accumulation in soil and grain of rice (cv. Naveen) to fly ash (FA) application was studied in a pot experiment during dry season 2011 in an Inceptisol. Fly ash was applied at a rate of zero per cent (FS), five per cent (FA5), ten per cent (FA10), twenty per cent (FA20), 40 per cent (FA40) and 100 per cent (FA100) on soil volume basis with nitrogen (N), phosphorus (P) and potassium (K) (40:20:20mg N:P:Kkg(-1) soil) with six replications. Heavy metals contents in soil and plant parts were analysed after harvest of crop. On the other hand, microbial population and soil enzymatic activities were analysed at panicle initiation stage (PI, 65 days after transplanting) of rice. There was no significant change in the concentration of zinc (Zn), iron (Fe), copper (Cu), manganese (Mn), cadmium (Cd) and chromium (Cr) with application of fly ash up to FA10. However, at FA100 there was significant increase of all metals concentration in soil than other treatments. Microorganisms differed in their response to the rate of FA application. Population of both fungi and actinomycetes decreased with the application of fly ash, while aerobic heterotrophic bacterial population did not change significantly up to FA40. On the other hand, total microbial activity measured in terms of Fluorescein diacetate (FDA) assay, and denitrifiers showed an increased trend up to FA40. However, activities of both alkaline and acid phosphatase were decreased with the application of FA. Application of FA at lower levels (ten to twenty per cent on soil volume basis) in soil enhanced micronutrients content, microbial activities and crop yield.


Asunto(s)
Ceniza del Carbón/farmacología , Metales Pesados/análisis , Oryza/química , Microbiología del Suelo , Suelo/química , Actinobacteria/aislamiento & purificación , Bacterias/aislamiento & purificación , Hongos/aislamiento & purificación , Nitrógeno/metabolismo , Residuos Sólidos
12.
Environ Monit Assess ; 187(5): 296, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25913623

RESUMEN

Integrated rice-fish culture, an age-old farming system, is a technology which could produce rice and fish sustainably at a time by optimizing scarce resource use through complementary use of land and water. An understanding of microbial processes is important for the management of farming systems as soil microbes are the living part of soil organic matter and play critical roles in soil C and N cycling and ecosystem functioning of farming system. Rice-based integrated farming system model for small and marginal farmers was established in 2001 at Central Rice Research Institute, Cuttack, Odisha. The different enterprises of farming system were rice-fish, fish-fingerlings, fruits, vegetables, rice-fish refuge, and agroforestry. This study was conducted with the objective to assess the soil physicochemical properties, microbial population, carbon and nitrogen fractions, soil enzymatic activity, and productivity of different enterprises. The effect of enterprises induced significant changes in the chemical composition and organic matter which in turn influenced the activities of enzymes (urease, acid, and alkaline phosphatase) involved in the C, N, and P cycles. The different enterprises of long-term rice-based farming system caused significant variations in nutrient content of soil, which was higher in rice-fish refuge followed by rice-fish enterprise. Highest microbial populations and enzymatic properties were recorded in rice-fish refuge system because of waterlogging and reduced condition prolonged in this system leading to less decomposition of organic matter. The maximum alkaline phosphatase, urease, and FDA were observed in rice-fish enterprise. However, highest acid phosphatase and dehydrogenase activity were obtained in vegetable enterprise and fish-fingerlings enterprise, respectively.


Asunto(s)
Agricultura/métodos , Monitoreo del Ambiente , Oryza/crecimiento & desarrollo , Suelo/química , Carbono/análisis , Ecosistema , Nitrógeno , Microbiología del Suelo , Tiempo , Ureasa , Verduras
13.
Environ Monit Assess ; 187(11): 679, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26450689

RESUMEN

Thermal power stations apart from being source of energy supply are causing soil pollution leading to its degradation in fertility and contamination. Fine particle and trace element emissions from energy production in coal-fired thermal power plants are associated with significant adverse effects on human, animal, and soil health. Contamination of soil with cadmium, nickel, copper, lead, arsenic, chromium, and zinc can be a primary route of human exposure to these potentially toxic elements. The environmental evaluation of surrounding soil of thermal power plants in Odisha may serve a model study to get the insight into hazards they are causing. The study investigates the impact of fly ash-fugitive dust (FAFD) deposition from coal-fired thermal power plant emissions on soil properties including trace element concentration, pH, and soil enzymatic activities. Higher FAFD deposition was found in the close proximity of power plants, which led to high pH and greater accumulation of heavy metals. Among the three power plants, in the vicinity of NALCO, higher concentrations of soil organic carbon and nitrogen was observed whereas, higher phosphorus content was recorded in the proximity of NTPC. Multivariate statistical analysis of different variables and their association indicated that FAFD deposition and soil properties were influenced by the source of emissions and distance from source of emission. Pollution in soil profiles and high risk areas were detected and visualized using surface maps based on Kriging interpolation. The concentrations of chromium and arsenic were higher in the soil where FAFD deposition was more. Observance of relatively high concentration of heavy metals like cadmium, lead, nickel, and arsenic and a low concentration of enzymatic activity in proximity to the emission source indicated a possible link with anthropogenic emissions.


Asunto(s)
Monitoreo del Ambiente , Metales Pesados/análisis , Centrales Eléctricas , Contaminantes del Suelo/análisis , Suelo/química , Carbón Mineral/análisis , Ceniza del Carbón/análisis , Ceniza del Carbón/química , Polvo/análisis , Contaminación Ambiental/análisis , Humanos , Análisis Multivariante , Contaminantes del Suelo/química
14.
Phys Rev Lett ; 113(8): 087203, 2014 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-25192122

RESUMEN

Noncollinear magnets provide essential ingredients for the next generation memory technology. It is a new prospect for the Heusler materials, already well known due to the diverse range of other fundamental characteristics. Here, we present a combined experimental and theoretical study of novel noncollinear tetragonal Mn(2)RhSn Heusler material exhibiting unusually strong canting of its magnetic sublattices. It undergoes a spin-reorientation transition, induced by a temperature change and suppressed by an external magnetic field. Because of the presence of Dzyaloshinskii-Moriya exchange and magnetic anisotropy, Mn(2)RhSn is suggested to be a promising candidate for realizing the Skyrmion state in the Heusler family.

15.
Environ Monit Assess ; 186(7): 4223-36, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24609455

RESUMEN

In order to identify the viable option of tillage practices in rice-maize-cowpea cropping system that could cut down soil carbon dioxide (CO2) emission, sustain grain yield, and maintain better soil quality in tropical low land rice ecology soil respiration in terms of CO2 emission, labile carbon (C) pools, water-stable aggregate C fractions, and enzymatic activities were investigated in a sandy clay loam soil. Soil respiration is the major pathway of gaseous C efflux from terrestrial systems and acts as an important index of ecosystem functioning. The CO2-C emissions were quantified in between plants and rows throughout the year in rice-maize-cowpea cropping sequence both under conventional tillage (CT) and minimum tillage (MT) practices along with soil moisture and temperature. The CO2-C emissions, as a whole, were 24 % higher in between plants than in rows, and were in the range of 23.4-78.1, 37.1-128.1, and 28.6-101.2 mg m(-2) h(-1) under CT and 10.7-60.3, 17.3-99.1, and 17.2-79.1 mg m(-2) h(-1) under MT in rice, maize, and cowpea, respectively. The CO2-C emission was found highest under maize (44 %) followed by rice (33 %) and cowpea (23 %) irrespective of CT and MT practices. In CT system, the CO2-C emission increased significantly by 37.1 % with respect to MT on cumulative annual basis including fallow. The CO2-C emission per unit yield was at par in rice and cowpea signifying the beneficial effect of MT in maintaining soil quality and reduction of CO2 emission. The microbial biomass C (MBC), readily mineralizable C (RMC), water-soluble C (WSC), and permanganate-oxidizable C (PMOC) were 19.4, 20.4, 39.5, and 15.1 % higher under MT than CT. The C contents in soil aggregate fraction were significantly higher in MT than CT. Soil enzymatic activities like, dehydrogenase, fluorescein diacetate, and ß-glucosidase were significantly higher by 13.8, 15.4, and 27.4 % under MT compared to CT. The soil labile C pools, enzymatic activities, and heterotrophic microbial populations were in the order of maize > cowpea > rice, irrespective of the tillage treatments. Environmental sustainability point of view, minimum tillage practices in rice-maize-cowpea cropping system in tropical low land soil could be adopted to minimize CO2-C emission, sustain yield, and maintain soil health.


Asunto(s)
Agricultura/métodos , Carbono/análisis , Microbiología del Suelo/normas , Suelo/química , Biomasa , Ciclo del Carbono , Dióxido de Carbono/análisis , Secuestro de Carbono , Ecosistema , Monitoreo del Ambiente , Fabaceae/crecimiento & desarrollo , Oryza/crecimiento & desarrollo , Temperatura , Zea mays/crecimiento & desarrollo
16.
Bull Environ Contam Toxicol ; 92(2): 160-4, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24362819

RESUMEN

The microbial biomass carbon (MBC) and carbon mineralization of fly ash (FA) amended soil at (0 %, 1.25 %, 2.5 %, 5 %, 10 % and 20 % FA; v/v) was investigated under laboratory conditions for 120 days at 60 % soil water-holding capacity and 25 ± 1°C temperature. The results demonstrated that soil respiration and microbial activities were not suppressed up to 2.5 % FA amendment and these activities decreased significantly at 10 % and 20 % FA treatment with respect to control. Application of 10 % and 20 % FA treated soils showed a decreasing trend of soil MBC with time; and the decrease was significant throughout the period of incubation. The study concluded that application of FA up to 2.5 % can thus be safely used without affecting the soil biological activity and thereby improve nutrient cycling in agricultural soils.


Asunto(s)
Ceniza del Carbón/toxicidad , Eliminación de Residuos , Microbiología del Suelo , Contaminantes del Suelo/toxicidad , Agricultura , Biomasa , Carbono/análisis , Carbono/química , Ceniza del Carbón/química , Suelo/química , Contaminantes del Suelo/química
17.
Bull Environ Contam Toxicol ; 93(1): 106-12, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24756333

RESUMEN

An experiment was conducted to assess the effect of fly ash deposition without and with (0.25, 0.50, 1.0 and 1.5 g m(-2 )day(-1)) foliar dusting on the photosynthesis, stomatal conductance, transpiration, leaf temperature, albedo and productivity of rice. Dusting of 0.5 g m(-2 )day(-1) fly ash and above significantly reduced the photosynthesis, stomatal conductance, transpiration and albedo. Panicle initiation and flowering stages were more influenced by the fly ash deposition as compared to active tillering stage. At higher rates of fly ash deposition, all growth and yield parameters were significantly influenced due to increased heat load and reduced intercellular CO2 concentration. A significant reduction of 12.3, 15.7 and 20.2 % in grain yield was recorded over control when fly ash was dusted at 0.5, 1.0 and 1.5 g m(-2 )day(-1), respectively.


Asunto(s)
Ceniza del Carbón/toxicidad , Contaminantes Ambientales/toxicidad , Oryza/efectos de los fármacos , Fotosíntesis/efectos de los fármacos , Oryza/crecimiento & desarrollo , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/crecimiento & desarrollo , Transpiración de Plantas/efectos de los fármacos , Temperatura
18.
Clin Ter ; 175(1): 42-46, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38358476

RESUMEN

Introduction: Significant progress has been made in understanding oocyte fertilization and early developmental stages through in vitro fertilization (IVF) techniques. However, irregularities such as conjoined oocytes and binucleate giant oocytes, which are exceptions to the normal rule of one diploid female gamete per follicle, can potentially lead to chromosomal disorders in embryos and are recommended to be excluded from IVF attempts. The formation of primordial follicles during ovarian development, known as follicle assembly, is a critical process that establishes the ovarian follicle reserve. Multi-oocyte follicles (MOFs) containing two or more oocytes have been observed in various species, including humans, and their clinical significance on fertility and reproductive health remains unclear. Genetic and environmental factors, such as gene knockout and exposure to endocrine disruptors, have been implicated in MOF formation, but the mechanisms are not fully understood and require further investigation. Material & Method: In this Observational study, 350 slides of ovarian tissues were scanned using an AI-based automated microscope, Grundium Ocus 20, and the TIFF images were stored in cloud storage. The slides were examined using third-party software, Pathcore Seeden Viewer, for morphometry of binovular follicles. Results: In our observational study, we examined 350 ovarian tissue slides in detail by using an AI-based microscope, uncovering 22 slides from seven different tissues with binovular and multinovular oocytes. These rare multi-oocyte follicles (MOFs) challenge the conventional one-oocyte-per-follicle paradigm. MOFs are likely formed when oocytes fail to separate during cortical sex cord proliferation, regulated by factors several molecular factorsas well as environmental factors. Discussion: Multiple Ovarian Follicles (MOFs) are rare phenomena where two or more oocytes exist in one follicle. They arise when oocytes fail to separate during ovarian development, which is governed by hormones such as follicle-stimulating hormone (FSH), inhibin, BMP-15, GDF-9, and GCNF. MOFs can be caused by dysregulation and exposure to chemicals such as diethylstilbestrol (DES) and isoflavones. Binovular oocytes, which occur when two oocytes are released during ovulation and are fertilised by different sperm, can result in non-identical twins, which are influenced by genetic and environmen-tal factors such as maternal age, heredity, hormonal imbalances, and assisted reproductive techniques such as in vitro fertilisation (IVF). Polynuclear oocytes with many nuclei can develop as a result of meiotic spindle defects and environmental influences. Identifying these oocyte types may aid in improving ART results by improving knowledge of the reasons of infertility and devising appropriate interventions.


Asunto(s)
Oocitos , Semen , Femenino , Masculino , Humanos , Fertilización In Vitro , Dietilestilbestrol
19.
Clin Ter ; 175(3): 181-183, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38767076

RESUMEN

Abstract: COVID-19 pandemic has increased the amount of plastic burden to environment and complexities of plastic waste management. Change in behavioral pattern with advent of this pandemic led to increased practice of hygiene and increased use of different types of personal protective equipment. Unfortunately, rapid rise in production of the PPEs (like Hazmat suit, gloves, etc.) and single-use plastics used in RT-PCR and other testing are the biggest source for increased non-biodegradable plastic waste leading to amplified burden on plastic waste management. A number of measures like prioritizing the policies directed towards changes at behavioral, social and institutional level need to be started. Also, reduction in plastic waste along with proper plastic waste management policies should be implemented. To prevent the transition from one pandemic to other; improvement in government policies with public private partnership are the need of the hour.


Asunto(s)
COVID-19 , Salud Global , Plásticos , COVID-19/prevención & control , COVID-19/epidemiología , Humanos , Pandemias , Equipo de Protección Personal/provisión & distribución , Administración de Residuos/métodos
20.
Nat Commun ; 15(1): 824, 2024 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-38280890

RESUMEN

Most superconductors have an isotropic, single component order parameter and are well described by the standard (BCS) theory for superconductivity. Unconventional, multiple-component superconductors are exceptionally rare and are much less understood. Here, we combine scanning tunneling microscopy and angle-resolved macroscopic transport for studying the candidate chiral superconductor, 4Hb-TaS2. We reveal quasi-periodic one-dimensional modulations in the tunneling conductance accompanied by two-fold symmetric superconducting critical field. The strong modulation of the in-plane critical field, Hc2, points to a nematic, unconventional order parameter. However, the imaged vortex core is isotropic at low temperatures. We suggest a model that reconciles this apparent discrepancy and takes into account previously observed spontaneous time-reversal symmetry breaking at low temperatures. The model describes a competition between a dominating chiral superconducting order parameter and a nematic one. The latter emerges close to the normal phase. Our results strongly support the existence of two-component superconductivity in 4Hb-TaS2 and can provide valuable insights into other systems with coexistent charge order and superconductivity.

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