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1.
Homeopathy ; 109(2): 65-78, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31652463

RESUMEN

BACKGROUND: Although the presence of starting materials in extreme dilutions of homeopathic medicines has been established, the physico-chemical changes of these materials induced by the manufacturing steps-that is, solid-solid mixing involving grinding (trituration) and slurry mixing involving impact (succussion), followed by dilution-are still unknown. METHODS: We subjected cupric oxide and zinc oxide nanoparticles (NPs) to the homeopathic processes of trituration and succussion, followed by dilution up to 6 cH. Particle image velocimetry was employed to analyze the fluid motion during succussion and its effect on the NPs. The resulting microstructural and chemical changes at different dilution steps were determined by X-ray photoelectron spectroscopy, Fourier-transform infrared spectroscopy and transmission electron microscopy. RESULTS: The succussion triggered multi-sized bubble generation and turbulent fluid motion up to a duration of 400 ms, with maximum average velocity of 0.23 m/s. Due to 1% transfer of kinetic energy from a moving eddy with this velocity, upon collision, the rate of temperature change in a particle of size 1 µm and 1 nm was predicted to rise by approximately 102 K/s and 106 K/s respectively. During trituration, the oxide NPs reduced to metals and did not aggregate by remaining within lactose, but they converted to oxidized finer NPs after impact. Silicate chains leached from the vial cross-linked after third dilution, forming large macro-particles and encapsulating the NPs that were retained and carried at higher dilution steps. CONCLUSION: The results showed that the NPs sustained significant rate of temperature change due to energy transfer from moving eddies during succussion. Different physico-chemical changes, such as size reduction, successive reduction and oxidation of NPs, and morphological changes, were achieved through trituration and succussion. The retention of NPs within cross-linked poly-siloxane chains reveals the importance of both the borosilicate glass vial and the ethanol solution during preparation of homeopathic medicines.


Asunto(s)
Cobre/química , Homeopatía , Nanopartículas del Metal/química , Óxido de Zinc/química , Humanos , Microscopía Electrónica de Transmisión , Espectroscopía de Fotoelectrones , Solventes , Espectroscopía Infrarroja por Transformada de Fourier
2.
Homeopathy ; 106(3): 135-144, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28844286

RESUMEN

BACKGROUND: High-potency homeopathic remedies, 30c and 200c have enormous dilution factors of 1060 and 10400 respectively. Therefore, the presence of physical entities in them is inconceivable. As a result, their efficacy is highly debated and often dismissed as a placebo. Despite several hypotheses postulated to explain the claimed homeopathic efficacy, none have satisfactorily answered the qualms of the sceptics. Against all beliefs and principles of conventional dilution, we have shown that nanoparticles (NPs) of the starting metals are unequivocally found in the 30c and 200c remedies at concentrations of a few pg/ml. In this paper, our aim was to answer the important question of whether such negligible metal concentrations elicit a biological response. METHODS: Metal-based homeopathic medicines (30c and 200c) were analysed at doses between 0.003%v/v and 10%v/v in in-vitro HepG2 cell-line. Upon treatment, cell response was estimated by MTT assay, FACS and total intracellular protein. Experiments were performed to discern whether the hormesis was a cell-activation or a proliferation effect. RESULTS: Remedies at doses containing a few femtograms/ml levels of the starting metals induced a proliferation-independent hormetic activation by increasing the intracellular protein synthesis. The metal concentrations (at fg/ml) were a billion-fold lower than the studies with synthetic NPs (at µg/ml). Further, we also highlight a few plausible mechanisms initiating a hormetic response at a billion-fold lower dose. CONCLUSIONS: Hormetic activation has been shown for the first time with standard homeopathic high-potency remedies. These findings should have a profound effect in understanding these extreme dilutions from a biological perspective.


Asunto(s)
Homeopatía/métodos , Materia Medica/uso terapéutico , Nanopartículas del Metal/uso terapéutico , Células Hep G2/efectos de los fármacos , Células Hep G2/metabolismo , Humanos
3.
RSC Adv ; 14(42): 30529-30542, 2024 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-39324038

RESUMEN

In this work, we explore the potential of polysulfone/ZIF-8 mixed matrix membranes (MMMs) for the enrichment of biogas to biomethane. To this end, we present data for these MMMs on permeability and selectivity as function of pressure and feed composition, at different loadings of ZIF-8. Specifically, we study dense polysulfone membranes prepared by solvent evaporation, with a ZIF-8 loading in the range 0.5-5 wt% for separation of CO2 from artificial mixtures of CO2 and CH4, and also biogas from an operating plant. The MMMs with 1 wt% filler loading gave the highest enhancement in permeability and selectivity, of 56.8% and 41% respectively, as compared to pure PSF membranes. At higher loadings, a tendency for the ZIF-8 particles to agglomerate was seen, which may compromise the ability of the filler to improve membrane performance. With mixed gases, increases in CO2 permeability of about 8 to 34% were observed depending on the gas composition, the enhancement being the higher, the lower the CO2 content. For biogas, permeability and selectivity of the 1% ZIF-8 loaded MMMs were found to be 14.6% and 39.64% lesser respectively than the pure gas values. The study thus throws light on the differences in membrane performance with mixtures as compared to ideal values obtained with pure gases and hence underlines the importance of lab-scale testing of the membranes with actual gas mixtures in the intended applications.

4.
Langmuir ; 28(45): 15864-75, 2012 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-23083226

RESUMEN

Extreme dilutions, especially homeopathic remedies of 30c, 200c, and higher potencies, are prepared by a process of serial dilution of 1:100 per step. As a result, dilution factors of 10(60), 10(400), or even greater are achieved. Therefore, both the presence of any active ingredient and the therapeutic efficacy of these medicines have been contentious because the existence of even traces of the starting raw materials in them is inconceivable. However, physicochemical studies of these solutions have unequivocally established the presence of the starting raw materials in nanoparticulate form even in these extreme (super-Avogadro, >10(23)) dilutions. In this article, we propose and validate a hypothesis to explain how nanoparticles are retained even at such enormous dilution levels. We show that once the bulk concentration is below a threshold level of a few nanograms/milliliter (ng/mL), at the end of each dilution step, all of the nanoparticles levitate to the surface and are accommodated as a monolayer at the top. This dominant population at the air-liquid interface is preserved and carried to the subsequent step, thereby forming an asymptotic concentration. Thus, all dilutions are only apparent and not real in terms of the concentrations of the starting raw materials.


Asunto(s)
Oro/química , Nanopartículas del Metal/química , Zinc/química , Lactosa/química , Espectrometría de Masas , Tamaño de la Partícula , Espectroscopía Infrarroja por Transformada de Fourier , Propiedades de Superficie
5.
Homeopathy ; 99(4): 231-42, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20970092

RESUMEN

Homeopathy is controversial because medicines in high potencies such as 30c and 200c involve huge dilution factors (106° and 104°° respectively) which are many orders of magnitude greater than Avogadro's number, so that theoretically there should be no measurable remnants of the starting materials. No hypothesis which predicts the retention of properties of starting materials has been proposed nor has any physical entity been shown to exist in these high potency medicines. Using market samples of metal-derived medicines from reputable manufacturers, we have demonstrated for the first time by Transmission Electron Microscopy (TEM), electron diffraction and chemical analysis by Inductively Coupled Plasma-Atomic Emission Spectroscopy (ICP-AES), the presence of physical entities in these extreme dilutions, in the form of nanoparticles of the starting metals and their aggregates.


Asunto(s)
Homeopatía , Técnicas de Dilución del Indicador , Mediciones Luminiscentes/métodos , Microscopía Electrónica de Transmisión/métodos , Nanopartículas/análisis , Soluciones/análisis , Calibración , Humanos , Nanopartículas/química , Nanopartículas/ultraestructura , Reproducibilidad de los Resultados , Soluciones/química , Dosimetría Termoluminiscente , Agua/química
6.
Data Brief ; 26: 104337, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31534989

RESUMEN

Data on the interfacial hydrolysis of trimesolyl chloride (TMC) is presented. The reaction is a side reaction in the process of interfacial polycondensation leading to polyamide films used in reverse osmosis, and affects the kinetics of film formation and properties of the film. We have developed (Behera and Suresh, 2019) a methodology for the kinetic study of this hydrolysis, and the data used it to determine and model the kinetics of hydrolysis of TMC are presented here. In order to provide the context, we first establish the circumstances under which it can be competitive with the main reaction. The data show that pH has a significant effect on the kinetics of hydrolysis, and the hydrolysis can be self-limiting under most circumstances. The presence of a surfactant, often present in such systems, can influence the kinetics in significant ways. The kinetic model has been tested against experimental data obtained with different initial TMC concentrations, and at different concentrations of a commonly used surfactant, Tween 85. The data here support the results and conclusions presented in the main paper i.e. (Behera and Suresh, 2019) and details, including parametric effects, are presented in this data-in-brief.

7.
Proc Math Phys Eng Sci ; 475(2224): 20180830, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31105457

RESUMEN

Carbon dioxide sequestration via carbonation of steel slags is a promising way of combining two waste products to create value. Understanding the dissolution kinetics of steel slags, which are alkaline and rich in calcium, in acidic media is essential to configure such a process. In this study, we seek to analyse the dissolution mechanism from experimental studies and develop a mathematical model considering the heterogeneous characteristics of slag. We found that the reduction in calcium extraction efficiency with an increase in particle size, which is normally associated with surface passivation or non-uniformity of samples, can be explained by considering the morphological features associated with the distribution of MgO-FeO (RO) phase in the calcium silicate matrix. We present a population balance model and show that the reduction in calcium extraction efficiency in coarse particle fractions is due to increased sporulation of the RO phase. The findings in the study suggest that the leaching of metal ions from slag is controlled by proton-promoted surface dissolution reaction, where the dependence of acid concentration follows the Langmuir-Hinshelwood adsorption isotherm. The model shows good agreement with a large set of parametric studies and demonstrates the importance of considering morphological features, as we progress towards development of a priori dissolution models for multi-mineral oxides and silicates.

8.
J Biosci Bioeng ; 96(5): 481-6, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-16233559

RESUMEN

A comprehensive model was developed to simulate Lactobacillus rhamnosus growth on a medium containing multiple limiting carbon sources. The strategy of optimizing specific growth rate to predict growth on multiple substrates was demonstrated. The model predictions were based on parameters obtained from L. rhamnosus growth on individual substrates. The model was able to simulate the growth, substrate consumption, product formation and specific growth rate profiles of L. rhamnosus accurately. The model prediction that co-metabolism of glucose and pyruvate enhances growth rate of and flavor production by the bacterium was experimentally verified.

9.
Zebrafish ; 11(4): 353-64, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24937310

RESUMEN

Zebrafish embryos are widely used as a model to monitor the effect of chemicals on their survival and hatching at different time epochs. This experimental design generates longitudinal data in which the observations for a given subject are correlated and they are statistically independent across the subjects. This particular nature of the observations suggests the use of generalized estimating equation (GEE) methodology for performing meaningful statistical analysis. However, it has been observed that the researchers working in this area have been routinely employing statistical methodologies such as analysis of variance (ANOVA) if the data are continuous and logit or probit models if the data are discrete. In our opinion, it is grossly incorrect to use these methods as they do not take into account the correlation structure mentioned above. The sole purpose of this article is to bring out this serious flaw clearly to the attention of the researchers. For illustration, we have studied the effects of two Ayurvedic bhasmas-Tamra bhasma and Suwarnamakshik bhasma-on survival and hatching of zebrafish embryos over certain time duration. The statistical analysis using GEE reveals a weak promotional effect of Suwarnamakshik bhasma and an inhibitory effect of Tamra bhasma on hatching.


Asunto(s)
Embrión no Mamífero/efectos de los fármacos , Metales/toxicidad , Pruebas de Toxicidad/métodos , Pez Cebra/metabolismo , Animales , Relación Dosis-Respuesta a Droga , Embrión no Mamífero/embriología , Medicina Ayurvédica , Modelos Teóricos , Factores de Tiempo , Pez Cebra/embriología
10.
Nanoscale Res Lett ; 6(1): 637, 2011 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-22209012

RESUMEN

Silicalite-poly(furfuryl alcohol) [PFA] composite membranes were prepared by solution casting of silicalite-furfuryl alcohol [FA] suspension on a porous polysulfone substrate and subsequent in situ polymerization of FA. X-ray diffraction, nitrogen sorption, thermogravimetric analysis, scanning electron microscopy, and energy-dispersive X-ray spectroscopy were used to characterize silicalite nanocrystals and silicalite-PFA composite membranes. The silicalite-PFA composite membrane with 20 wt.% silicalite loading exhibits good oxygen/nitrogen selectivity (4.15) and high oxygen permeability (1,132.6 Barrers) at 50°C. Silicalite-PFA composite membranes are promising for the production of oxygen-enriched air for various applications.

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