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1.
ACS Omega ; 9(20): 22476-22487, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38799333

RESUMEN

PPh3O.hemihydrate polymorphs and 11 assorted PPh3O cocrystals collectively constitute a reliable stock to pursue a systematic analysis aiming to investigate the impacts of some vital issues on the TPPO.H-bond donor aggregates. The issues highlighted herein are (i) effect of varying acidity of H-bond donors on the degeneracy of lone pairs of the H-bond acceptor (PPh3O), (ii) effectiveness of the |V(r)|/G(r) and H(r)/ρ(r) parameters as a covalency metric, (iii) 3c-4e bonding in the covalent PPh3O.nitric acid cocrystal, (iv) salient features of H-bond interaction energy and an interplay of its components, (v) an intrinsic bond strength scale for the PPh3O cocrystals, and (vi) reliable empirical relations between several bond descriptors for a quick estimation of interaction energy. To be specific about point (vi), we have propounded two promising avenues for a fast semiquantitative calculation of interaction energy from an endearing nonenergetic parameter, viz., bond length: dO-H···O → ρBCP (MAPE = 2.36%) → ESAPT0 (MAPE = 9.26%), and dO-H···O → IBSI (MAPE = 1.87%) → ESAPT0 (MAPE = 9.66%). All the aforesaid issues have been explored in detail through the QTAIM, NBO, and IBSI analyses (M06-2X-D3/def2-TZVP level), as well as by the SAPT study at the SAPT0/aug-cc-pVDZ platform. The statistically valid correlation studies can be particularly conducive for practical purposes as a transformative extension of the established facts into postulates for the unknown cocrystals.

2.
RSC Adv ; 13(44): 30586-30605, 2023 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-37859781

RESUMEN

The treatment of environmental pollution by employing microorganisms is a promising technology, termed bioremediation, which has several advantages over the other established conventional remediation techniques. Consequently, there is an urgent inevitability to develop pragmatic techniques for bioremediation, accompanied by the potency of detoxifying soil environments completely. The bioremediation of contaminated soils has been shown to be an alternative that could be an economically viable way to restore polluted soil. The soil environments have long been extremely polluted by a number of contaminants, like agrochemicals, polyaromatic hydrocarbons, heavy metals, emerging pollutants, etc. In order to achieve a quick remediation overcoming several difficulties the utility of biosurfactants became an excellent advancement and that is why, nowadays, the biosurfactant mediated recovery of soil is a focus of interest to the researcher of the environmental science field specifically. This review provides an outline of the present scenario of soil bioremediation by employing a microbial biosurfactant. In addition to this, a brief account of the pollutants is highlighted along with how they contaminate the soil. Finally, we address the future outlook for bioremediation technologies that can be executed with a superior efficiency to restore a polluted area, even though its practical applicability has been cultivated tremendously over the few decades.

3.
PLoS One ; 18(9): e0291753, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37725616

RESUMEN

We describe changes in the cropland distribution for physiographic and bioregions of continental Ecuador between 2000 and 2016 using Landsat satellite data and government statistics. The cloudy conditions in Ecuador are a major constraint to satellite data analysis. We developed a two-stage cloud filtering algorithm to create cloud-free multi-temporal Landsat composites that were used in a Random Forest model to identify cropland. The overall accuracy of the model was 78% for the Coast region, 86% for the Andes, and 98% for the Amazon region. Cropland density was highest in the coastal lowlands and in the Andes between 2500 and 4400 m. During this period, cropland expansion was most pronounced in the Páramo, Chocó Tropical Rainforests, and Western Montane bioregions. There was no cropland expansion detected in the Eastern Foothill forests bioregion. The satellite data analysis further showed a small contraction of cropland (4%) in the Coast physiographic region, and cropland expansion in the Andes region (15%), especially above 3500m, and in the Amazon region (57%) between 2000 and 2016. The government data showed a similar contraction for the Coast (7%) but, in contrast with the satellite data, they showed a large agricultural contraction in the Andes (39%) and Amazon (50%). While the satellite data may be better at estimating relative change (trends), the government data may provide more accurate absolute numbers in some regions, especially the Amazon because separating pasture and tree crops from forest with satellite data is challenging. These discrepancies illustrate the need for careful evaluation and comparison of data from different sources when analyzing land use change.


Asunto(s)
Agricultura , Algoritmos , Ecuador , Productos Agrícolas , Análisis de Datos
4.
Heliyon ; 9(5): e15965, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37251844

RESUMEN

Background: In India, facility-based surveillance for congenital rubella syndrome (CRS) was initiated in 2016 to estimate the burden and monitor the progress made in rubella control. We analyzed the surveillance data for 2016-2021 from 14 sentinel sites to describe the epidemiology of CRS. Method: We analyzed the surveillance data to describe the distribution of suspected and laboratory confirmed CRS patients by time, place and person characteristics. We compared clinical signs of laboratory confirmed CRS and discarded case-patients to find independent predictors of CRS using logistic regression analysis and developed a risk prediction model. Results: During 2016-21, surveillance sites enrolled 3940 suspected CRS case-patients (Age 3.5 months, SD: 3.5). About one-fifth (n = 813, 20.6%) were enrolled during newborn examination. Of the suspected CRS patients, 493 (12.5%) had laboratory evidence of rubella infection. The proportion of laboratory confirmed CRS cases declined from 26% in 2017 to 8.7% in 2021. Laboratory confirmed patients had higher odds of having hearing impairment (Odds ratio [OR] = 9.5, 95% confidence interval [CI]: 5.6-16.2), cataract (OR = 7.8, 95% CI: 5.4-11.2), pigmentary retinopathy (OR = 6.7, 95 CI: 3.3-13.6), structural heart defect with hearing impairment (OR = 3.8, 95% CI: 1.2-12.2) and glaucoma (OR = 3.1, 95% CI: 1.2-8.1). Nomogram, along with a web version, was developed. Conclusions: Rubella continues to be a significant public health issue in India. The declining trend of test positivity among suspected CRS case-patients needs to be monitored through continued surveillance in these sentinel sites.

5.
PLoS One ; 16(10): e0258215, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34624022

RESUMEN

Agricultural index insurance contracts increasingly use remote sensing data to estimate losses and determine indemnity payouts. Index insurance contracts inevitably make errors, failing to detect losses that occur and issuing payments when no losses occur. The quality of these contracts and the indices on which they are based, need to be evaluated to assess their fitness as insurance, and to provide a guide to choosing the index that best protects the insured. In the remote sensing literature, indices are often evaluated with generic model evaluation statistics such as R2 or Root Mean Square Error that do not directly consider the effect of errors on the quality of the insurance contract. Economic analysis suggests using measures that capture the impact of insurance on the expected economic well-being of the insured. To bridge the gap between the remote sensing and economic perspectives, we adopt a standard economic measure of expected well-being and transform it into a Relative Insurance Benefit (RIB) metric. RIB expresses the welfare benefits derived from an index insurance contract relative to a hypothetical contract that perfectly measures losses. RIB takes on its maximal value of one when the index contract offers the same economic benefits as the perfect contract. When it achieves none of the benefits of insurance it takes on a value of zero, and becomes negative if the contract leaves the insured worse off than having no insurance. Part of our contribution is to decompose this economic well-being measure into an asymmetric loss function. We also argue that the expected well-being measure we use has advantages over other economic measures for the normative purpose of insurance quality ascertainment. Finally, we illustrate the use of the RIB measure with a case study of potential livestock insurance contracts in Northern Kenya. We compared 24 indices that were made with 4 different statistical models and 3 remote sensing data sources. RIB for these indices ranged from 0.09 to 0.5, and R2 ranged from 0.2 to 0.51. While RIB and R2 were correlated, the model with the highest RIB did not have the highest R2. Our findings suggest that, when designing and evaluating an index insurance program, it is useful to separately consider the quality of a remote sensing-based index with a metric like the RIB instead of a generic goodness-of-fit metric.


Asunto(s)
Agricultura , Seguro , Tecnología de Sensores Remotos , Animales , Composición Familiar , Beneficios del Seguro , Ganado , Modelos Estadísticos , Mortalidad
6.
PLoS One ; 14(12): e0225555, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31826001

RESUMEN

Declines in agricultural biodiversity associated with modern farming practices may negatively affect the sustainability of agro-ecosystems, but formal knowledge of historical variation in spatio-temporal variation of agro-biodiversity is limited. We used time series of national (1947-2014) and district-level (1956-2008) crop distribution data for India to show that despite strong agricultural intensification after 1960, the average crop species diversity at the district level was stable, but increased at the country-level. While there was a decline in diversity in the major rice and wheat producing regions of northwestern India, associated with intensification of the production of these crops, diversity in western and southern India increased due to expansion of oilseeds and horticultural crops that replaced millet and sorghum. These opposite, but related, trends in crop-level diversity at the sub-national level partially canceled each other out at national level, but there nevertheless was a noticeable increase in overall crop diversity in India during this time period. Our results illustrate how patterns of change in crop diversity need to be considered at different levels of aggregation, and how a decrease in diversity associated with intensification and specialization in one area, may be associated with increased diversity elsewhere, and that support for intensive agriculture with relatively low crop diversity in some regions may be associated with an increase in crop diversity in other regions and at a higher level of aggregation.


Asunto(s)
Biodiversidad , Producción de Cultivos/estadística & datos numéricos , Productos Agrícolas/historia , Grano Comestible/historia , Producción de Cultivos/historia , Producción de Cultivos/métodos , Granjas/historia , Granjas/estadística & datos numéricos , Geografía , Historia del Siglo XX , Historia del Siglo XXI , India , Mijos , Oryza , Sorghum , Análisis Espacio-Temporal , Triticum
8.
J Clin Diagn Res ; 11(5): SD03-SD04, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28658867

RESUMEN

Recurrent bacterial meningitis is very rare phenomenon in paediatric age group. Finding the aetiology of recurrent meningitis often poses diagnostic challenge to clinicians. Among the several aetiologies, structural deficiencies at the base of skull, congenital or acquired, are readily correctable ones and hence it's imperative to find out the location of the gap in order to surgically repair it. We report the diagnostic dilemma faced while managing a 15-year-old boy with recurrent pneumococcal meningitis. Aetiology could only be found after exclusion of immunodeficiency and performing a series of imaging studies. CT cisternogram clinched the diagnosis and patient was cured successfully. A single imaging modality, be it CT/MRI scan, although proven to be better than others according to literature, might not be sufficient while finding the cause of recurrent bacterial meningitis in an immunocompetent host.

11.
Artículo en Inglés | MEDLINE | ID: mdl-24468985

RESUMEN

In aqueous acidic media, picolinic acid, 2,2'-bipyridine and 1,10-phenanthroline promoted Cr(VI) oxidation of 1-butanol produces 1-butanal. 1-butanal is separated from mixture by fractional distillation. The anionic surfactant (SDS) and neutral surfactant (TX-100) accelerate the process while the cationic surfactant (CPC) retards the reaction. Combination of bipy and SDS is the best choice for chromic acid oxidation of 1-butanol to 1-butanal in aqueous media.


Asunto(s)
1-Butanol/química , Aldehídos/química , Cromatos/química , Micelas , Temperatura , Agua/química , Catálisis , Cromo/análisis , Ésteres/análisis , Oxidación-Reducción , Ácidos Picolínicos/química , Espectroscopía de Protones por Resonancia Magnética , Protones , Soluciones , Solventes/química , Espectrofotometría Ultravioleta , Tensoactivos/química , Factores de Tiempo
12.
Artículo en Inglés | MEDLINE | ID: mdl-24317255

RESUMEN

Kinetic data for oxidation of D-sorbitol to glucose by hexavalent chromium in aqueous medium and aqueous surfactant medium (SDS, TX-100) have been reported. Effect of promoter such as PA, bipy and phenanthroline on the reaction has been investigated. The reaction is performed under pseudo first order condition with an excess of substrate over the oxidant. The reaction is first order with respect to substrate and oxidant. The micelles have a catalytic effect on the reaction. Combination of phen and TX-100 produces almost twelve times increase in rate of oxidation.


Asunto(s)
Glucosa/química , Micelas , Sorbitol/química , Catálisis , Cromo/química , Semivida , Microscopía Electrónica de Transmisión , Oxidantes/química , Factores de Tiempo
13.
Artículo en Inglés | MEDLINE | ID: mdl-23978739

RESUMEN

Picolinic acid, 2,2'-bipyridine and 1,10-phenanthroline promoted Cr(VI) oxidation of D-galactose to D-galactonic acid in three representative aqueous micellar media has been studied. The anionic surfactant (SDS) accelerated the rate of reaction while the cationic surfactant (CPC) and neutral surfactant (TX-100) retarded the reaction rate. Combination of bipy and SDS is the best choice for chromic acid oxidation of D-galactose to D-galactonic acid in aqueous media although 1,10-phenanthroline is best promoter in absence of micellar catalyst.


Asunto(s)
2,2'-Dipiridil/química , Cromatos/química , Galactosa/química , Fenantrolinas/química , Ácidos Picolínicos/química , Azúcares Ácidos/química , Catálisis , Micelas , Oxidación-Reducción , Temperatura , Agua/química
14.
Artículo en Inglés | MEDLINE | ID: mdl-23501718

RESUMEN

The kinetics of oxidation of benzaldehyde by chromic acid in aqueous and aqueous surfactant (sodium dodecyl sulfate, SDS, alkyl phenyl polyethylene glycol, Triton X-100 and N-cetylpyridinium chloride, CPC) media have been investigated in the presence of promoter at 303 K. The pseudo-first-order rate constants (kobs) were determined from a logarithmic plot of absorbance as a function time. The rate constants were found to increase with introduction of heteroaromatic nitrogen base promoters such as Picolinic acid (PA), 2,2'-bipyridine (bipy) and 1,10-phenanthroline (phen). The product benzoic acid has been characterized by conventional melting point experiment, NMR, HRMS and FTIR spectral analysis. The mechanism of both unpromoted and promoted reaction path has been proposed for the reaction. In presence of the anionic surfactant SDS, cationic surfactant CPC and neutral surfactant TX-100 the reaction can undergo simultaneously in both aqueous and micellar phase with an enhanced rate of oxidation in the micellar phase. Both SDS and TX-100 produce normal micellar effect whereas CPC produce reverse micellar effect in the presence of benzaldehyde. The observed net enhancement of rate effects has been explained by considering the hydrophobic and electrostatic interaction between the surfactants and reactants. SDS and bipy combination is the suitable one for benzaldehyde oxidation.


Asunto(s)
Benzaldehídos/química , Ácido Benzoico/química , Cromo/química , Micelas , Tensoactivos/química , 2,2'-Dipiridil/química , Catálisis , Cetilpiridinio/química , Cinética , Oxidación-Reducción , Fenantrolinas/química , Polietilenglicoles/química , Dodecil Sulfato de Sodio/química
15.
Spectrochim Acta A Mol Biomol Spectrosc ; 101: 294-305, 2013 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-23123236

RESUMEN

Oxidation of propan-2-ol to acetone was carried out in aqueous media at room temperature. The effect of promoter (PA, bpy, phen), micellar catalyst (SDS, CPC, TX-100) and their combination has been studied. The reactions were performed under the condition [Propan-2-ol]T≫[Cr(VI)]T at 30°C. Then kobs and half life of all the reaction were determined to identify which promoter and which combination are the most effective for this oxidation. Among the promoters phen accelerates the reaction most in aqueous media. In absence of promoters anionic surfactant SDS increases the rate more effectively than neutral surfactant TX-100. CPC retards the rate in comparison to aqueous media. The rate of the oxidation is highest in presence of the combination of bpy and SDS.


Asunto(s)
2-Propanol/química , Acetona/química , Cromatos/química , Agua/química , Catálisis , Micelas , Oxidación-Reducción , Polietilenglicoles/química , Dodecil Sulfato de Sodio/química , Tensoactivos/química
16.
Environ Monit Assess ; 185(4): 3313-25, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22828979

RESUMEN

Urbanisation is a ubiquitous phenomenon with greater prominence in developing nations. Urban expansion involves land conversions from vegetated moisture-rich to impervious moisture-deficient land surfaces. The urban land transformations alter biophysical parameters in a mode that promotes development of heat islands and degrades environmental health. This study elaborates relationships among various environmental variables using remote sensing dataset to study spatio-temporal footprint of urbanisation in Surat city. Landsat Thematic Mapper satellite data were used in conjugation with geo-spatial techniques to study urbanisation and correlation among various satellite-derived biophysical parameters, [Normalised Difference Vegetation Index, Normalised Difference Built-up Index, Normalised Difference Water Index, Normalised Difference Bareness Index, Modified NDWI and land surface temperature (LST)]. Land use land cover was prepared using hierarchical decision tree classification with an accuracy of 90.4 % (kappa = 0.88) for 1990 and 85 % (kappa = 0.81) for 2009. It was found that the city has expanded over 42.75 km(2) within a decade, and these changes resulted in elevated surface temperatures. For example, transformation from vegetation to built-up has resulted in 5.5 ± 2.6 °C increase in land surface temperature, vegetation to fallow 6.7 ± 3 °C, fallow to built-up is 3.5 ± 2.9 °C and built-up to dense built-up is 5.3 ± 2.8 °C. Directional profiling for LST was done to study spatial patterns of LST in and around Surat city. Emergence of two new LST peaks for 2009 was observed in N-S and NE-SW profiles.


Asunto(s)
Monitoreo del Ambiente/métodos , Análisis Espacio-Temporal , Urbanización/tendencias , Ciudades/estadística & datos numéricos , India , Tecnología de Sensores Remotos , Nave Espacial , Temperatura
17.
J Osteoporos ; 2011: 426863, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21772972

RESUMEN

Aim. This paper aimed to examine the chemoprotective actions of aqueous black tea extract (BTE) against nonalcoholic steatohepatitis- (NASH-) induced skeletal changes in rats. Material. Wistar rats (body wt. 155-175 g) of both sexes, aged 4-5 months, were randomly assigned to 3 groups; Group A (control), Group B (60% high-fat diet; HFD), and Group C (HFD + 2.5% BTE). Methods. Several urinary (calcium, phosphate, creatinine, and calcium-to-creatinine ratio) serum (alkaline phosphatase and serum tartrate-resistant acid phosphatase), and molecular markers of bone turnover (receptor activator of NF-κB ligand (RANKL), osteoprotegerin (OPG), and estrogen) were tested. Also, several bone parameters (bone density, bone tensile strength, bone mineral content, and bone histology) and calcium homeostasis were checked. Results. Results indicated that HFD-induced alterations in urinary, serum, and bone parameters as well as calcium homeostasis, all could be significantly ameliorated by BTE supplementation. Conclusion. Results suggest a potential role of BTE as a protective agent against NASH-induced changes in bone metabolism in rats.

18.
Environ Toxicol Pharmacol ; 31(1): 107-18, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21787675

RESUMEN

The present study was aimed to test the hypothesis that inorganic phosphate may reduce arsenic toxicity by decreasing its intestinal transference. Co-administration of inorganic phosphate (6.56 M) and arsenic (6.07 mM) in the intestinal loops of rats, in situ, caused significant reduction of arsenic transference. Short-term arsenic exposure (3mg/kg body weight/day for 30 days) caused liver damage evidenced by activities of liver enzymes and necroinflammatory changes. These effects of arsenic were coupled with enhanced mitochondrial swelling, inhibition of cytochrome c oxidase, Ca(2+)-ATPase, a decrease in mitochondrial calcium content, changes in indices of hepatic mitochondrial oxidative stress and iNOS expression. Arsenic also increased hepatic caspase 3 activity and DNA fragmentation. All these apoptosis-related molecular changes caused by arsenic could be alleviated by supplementation with inorganic phosphate, which likely suggests a protective role of phosphate against arsenic-induced hepatotoxic changes.


Asunto(s)
Arsénico/antagonistas & inhibidores , Arsénico/toxicidad , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Enfermedad Hepática Inducida por Sustancias y Drogas/prevención & control , Mitocondrias Hepáticas/efectos de los fármacos , Mitocondrias Hepáticas/patología , Fosfatos/uso terapéutico , Fósforo Dietético/farmacología , Venenos/toxicidad , Animales , Intoxicación por Arsénico/metabolismo , Caspasa 3/metabolismo , Catalasa/metabolismo , Fragmentación del ADN/efectos de los fármacos , Suplementos Dietéticos , Radical Hidroxilo/metabolismo , Mucosa Intestinal/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Hígado/patología , Masculino , Membranas Mitocondriales/efectos de los fármacos , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo , Ratas , Ratas Wistar , Superóxido Dismutasa/metabolismo
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