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1.
Pharm Dev Technol ; 28(2): 176-189, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36688412

RESUMO

The current study aimed to investigate drug carrier miscibility in pharmaceutical solid dispersions (SD) and include the effervescent system, i.e. Effervescence-induced amorphous solid dispersions (ESD), to enhance the solubility of a poorly water-soluble Glibenclamide (GLB). Kollidon VA 64, PEG-3350, and Gelucire-50/13 were selected as the water-soluble carriers. The miscibility of the drug-carrier was predicted by molecular dynamics simulation, Hansen solubility parameters, Flory-Huggins theory, and Gibb's free energy. Solid dispersions were prepared by microwave, solvent evaporation, lyophilization, and Hot Melt Extrusion (HME) methods. The prepared solid dispersions were subjected to solubility, in-vitro dissolution, and other characterization studies. The in-silico and theoretical approach suggested that the selected polymers exhibited better miscibility with GLB. Solid-state characterizations like FTIR and 1H NMR proved the formation of intermolecular hydrogen bonding between the drug and carriers, which was comparatively higher in ESDs than SDs. DSC, PXRD, and microscopic examination of GLB and SDs confirmed the amorphization of GLB, which was higher in ESDs than SDs. Gibb's free energy concept suggested that the prepared solid dispersions will be stable at room temperature. Ex-vivo intestinal absorption study on optimized ESDs prepared with Kollidon VA64 using the HME technique exhibited a higher flux and permeability coefficient than the pure drug suggesting a better drug delivery. The drug-carrier miscibility was successfully studied in SDs of GLB. The addition of the effervescent agent further enhanced the solubility and dissolution of GLB. Additionally, this might exhibit a better bioavailability, confirmed by ex-vivo intestinal absorption study.


Assuntos
Polímeros , Água , Solubilidade , Preparações Farmacêuticas , Composição de Medicamentos/métodos , Polímeros/química , Portadores de Fármacos/química
2.
Sensors (Basel) ; 22(15)2022 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-35957321

RESUMO

In wine tasting, tasters commonly swirl their glasses before inhaling the headspace above the wine. However, the consequences of wine swirling on the chemical gaseous headspace inhaled by tasters are barely known. In champagne or sparkling wine tasting, starting from the pouring step, gas-phase carbon dioxide (CO2) is the main gaseous species that progressively invades the glass headspace. We report the development of a homemade orbital shaker to replicate wine swirling and the upgrade of a diode laser sensor (DLS) dedicated to monitoring gas-phase CO2 in the headspace of champagne glasses under swirling conditions. We conduct a first overview of gas-phase CO2 monitoring in the headspace of a champagne glass, starting from the pouring step and continuing for the next 5 min, with several 5 s swirling steps to replicate the natural orbital movement of champagne tasters. The first results show a sudden drop in the CO2 concentration in the glass headspace, probably triggered by the liquid wave traveling along the glass wall following the action of swirling the glass.


Assuntos
Vinho , Dióxido de Carbono/análise , Gases , Lasers Semicondutores , Paladar , Vinho/análise
3.
AAPS PharmSciTech ; 23(8): 284, 2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36253571

RESUMO

The present research aims to investigate the miscibility, physical stability, solubility, and dissolution rate of a poorly water-soluble glibenclamide (GLB) in solid dispersions (SDs) with hydrophilic carriers like PEG-1500 and PEG-50 hydrogenated palm glycerides (Acconon). Mathematical theories such as Hansen solubility parameters, Flory Huggins theory, Gibbs free energy, and the in silico molecular dynamics simulation study approaches were used to predict the drug-carrier miscibility. To increase the solubility further, the effervescence technique was introduced to the conventional solid dispersions to prepare effervescent solid dispersions (ESD). Solid dispersions (SDs) were prepared by microwave, solvent evaporation, lyophilization, and hot melt extrusion (HME) techniques and tested for different characterization parameters. The theoretical and in silico parameters suggested that GLB would show good miscibility with the selected carriers under certain conditions. Intermolecular hydrogen bonding between the drug and carrier(s) was confirmed by Fourier transform infrared spectroscopy and proton nuclear magnetic resonance spectroscopy. Solid-state characterizations like powder X-ray diffraction, differential scanning calorimetry, and microscopy confirm the amorphous nature of SDs. The addition of the effervescent agent improved the amorphous nature, due to which the solubility and drug release rate was increased. In vitro and ex vivo intestinal absorption studies showed improved flux and permeability than the pure drug, suggesting an enhanced drug delivery. The GLB solubility, dissolution, and stability were greatly enhanced by the SD and ESD technology.


Assuntos
Portadores de Fármacos , Glibureto , Varredura Diferencial de Calorimetria , Portadores de Fármacos/química , Composição de Medicamentos/métodos , Excipientes , Glicerídeos , Pós , Prótons , Solubilidade , Solventes , Espectroscopia de Infravermelho com Transformada de Fourier , Água , Difração de Raios X
4.
Anthropol Med ; 29(3): 289-304, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34913756

RESUMO

Early in South Africa's HIV/AIDS crisis, entertainment education emerged as a powerful vehicle for communicating health and social messaging to combat the epidemic. Applied theatre now accounts for the majority of arts-based HIV interventions in sub-Saharan Africa, and continues a history of theatre for social change in South Africa in particular. While much has been written about the dramaturgical and communication theories that support such interventions, the role of music, a formidable tool in the applied theatre intervention arsenal, has received considerably less attention within applied arts intervention scholarship. This paper draws from Durkheim's collective effervescence to propose a theoretical approach to music within the creation and maintenance of effervescent assemblies that is being employed by HIV/AIDS interventions to encourage participation in HIV testing. The theoretical model of musical effervescence is situated within ethnographic fieldwork conducted while accompanying an applied HIV/AIDS theatre company on a national tour of South Africa.


Assuntos
Síndrome da Imunodeficiência Adquirida , Infecções por HIV , Música , Síndrome da Imunodeficiência Adquirida/epidemiologia , Antropologia Médica , Relações Comunidade-Instituição , Infecções por HIV/epidemiologia , Infecções por HIV/terapia , Humanos , África do Sul/epidemiologia
5.
J Sep Sci ; 44(24): 4313-4326, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34661968

RESUMO

To simultaneously and efficiently extract pollutants with differential polarities, we herein fabricated and characterized a multifunctional nanocomposite. The novel nanohybrids used NiFe2 O4 as magnetic cores, and NH2 -MIL-101(Al), ß-cyclodextrin and graphene oxide as functional components combined with magnetic cores. With the aid of graphene oxide's large π-conjugated system, NH2 -MIL-101(Al)'s strong adsorption to moderately/strongly polar chemicals, and ß-cyclodextrin's specific recognition effect, the nanohybrids realized synergistically efficient extraction of polyaromatic hydrocarbons and bisphenols with a logKow range of 3-6. Combined with acidic and alkaline sources, the nanohybrids-based effervescent tablets were prepared. Based on effervescent reaction-enhanced nanohybrids-based efficient adsorption/extraction and high performance liquid chromatography and fluorescence detection, we successfully developed an excellent microextraction method for the simultaneous determination of both polyaromatic hydrocarbons and bisphenols in roasted meat samples. Several important variables were optimized as follows: Na2 CO3 and tartaric acid as acidic and alkaline sources, 900 µLof the mixed solvent (acetone and hexane at 2:1 by v/v) as the eluent, 5 min of elution time. Under optimized conditions, the novel method gave low limits of detection (0.07-0.30 µg kg-1 ), satisfactory recoveries (86.9-103.9%), and high precision (relative standard deviations of 1.9-6.7%) in roasted lamb, beef, pork, chicken, and sausage samples.


Assuntos
Contaminação de Alimentos/análise , Magnetismo , Produtos da Carne/análise , Nanoestruturas , Compostos Orgânicos/isolamento & purificação , Microextração em Fase Sólida/métodos , Compostos Benzidrílicos/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Limite de Detecção , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Fenóis/isolamento & purificação , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Espectrometria de Fluorescência/métodos
6.
Molecules ; 26(15)2021 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-34361583

RESUMO

The persistence of effervescence and foam collar during a Champagne or sparkling wine tasting constitute one, among others, specific consumer preference for these products. Many different factors related to the product or to the tasting conditions might influence their behavior in the glass. However, the underlying factor behind the fizziness of these wines involves a second in-bottle alcoholic fermentation, also well known as the prise de mousse. The aim of this study was to assess whether a low temperature (13 °C) or a high temperature (20 °C) during the in-bottle fermentation might have an impact on the effervescence and the foaming properties (i.e., collar height and bubble size) of three French sparkling wines (a Crémant de Loire and two Champagne wines), under standard tasting conditions. Our results showed that sparkling wines elaborated at 13 °C and served in standard tasting conditions (i.e., 100 mL, 18 °C) had better ability to keep the dissolved CO2 (between 0.09 and 0.30 g/L) in the liquid phase than those elaborated at 20 °C (with P < 0.05). Most interestingly, we also observed, for the Crémant de Loire and for one Champagne wine, that the lower the temperature of the prise de mousse, the smaller (with P < 0.05) the bubbles in the foam collar throughout the wine tasting.


Assuntos
Dióxido de Carbono/química , Temperatura Baixa , Vinho
7.
J Sep Sci ; 43(12): 2419-2428, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32175682

RESUMO

In this work, a novel extraction technique based on the effervescence-assisted dispersion and magnetic recovery of attapulgite/polypyrrole sorbents was developed for determining the concentrations of five pyrethroids in honey samples. The magnetic nanoparticles were synthesized by a one-pot method. Several experimental parameters that affected the extraction efficiency, including the dispersion conditions, pH, ionic strength, and desorption conditions, were investigated. Under optimal conditions, the calibration curves for the five pyrethroids in honey samples exhibited good linearity, with r2 values ranging from 0.9979 to 0.9990. The limits of detection varied between 0.21 and 0.34 µg/L. Satisfactory recoveries of 81.42-106.73% with intra- and interday relative standard deviations of less than 6.94 and 10.89%, respectively, were obtained. Moreover, the sorbents exhibited acceptable batch-to-batch repeatability in the range of 5.06-15.01%, and each sorbent could be reused for up to four extraction cycles without a significant loss in the extraction recovery.


Assuntos
Mel/análise , Compostos de Magnésio/química , Nanocompostos/química , Polímeros/química , Piretrinas/análise , Pirróis/química , Compostos de Silício/química , Extração em Fase Sólida , Adsorção , Fenômenos Magnéticos , Tamanho da Partícula , Propriedades de Superfície
8.
Molecules ; 25(24)2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-33371453

RESUMO

Dispersive microextraction techniques are key in the analytical sample treatment context as they combine a favored thermodynamics and kinetics isolation of the target analytes from the sample matrix. The dispersion of the extractant in the form of tiny particles or drops, depending on the technique, into the sample enlarges the contact surface area between phases, thus enhancing the mass transference. This dispersion can be achieved by applying external energy sources, the use of chemicals, or the combination of both strategies. Effervescence-assisted microextraction emerged in 2011 as a new alternative in this context. The technique uses in situ-generated carbon dioxide as the disperser, and it has been successfully applied in the solid-phase and liquid-phase microextraction fields. This minireview explains the main fundamentals of the technique, its potential and the main developments reported.


Assuntos
Microextração em Fase Líquida/métodos , Dióxido de Carbono/química , Cinética , Termodinâmica
9.
J Sep Sci ; 42(18): 2993-3001, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31301158

RESUMO

A novel dispersive liquid-liquid microextraction that combines self-induced acid-base effervescent reaction and manual shaking, coupled with ultra high performance liquid chromatography with tandem mass spectrometry was developed for simultaneous determination of ten neonicotinoid insecticides and metabolites in orange juice. An innovative aspect of this method was the utilization of the acidity of the juice for a self-reaction between acidic components contained in the juice sample and added sodium carbonate which generated carbon dioxide bubbles in situ, accelerating the analytes transfer to the extractant of 1-undecanol. The total acid content of juice sample was measured to produce the maximum amount of bubbles with minimum usage of carbonate. Manual shaking was subsequently adopted and was proven to enhance the extraction efficiency. The factors affecting the performance, including the type and the amount of the carbon dioxide source and extractant, and ionic strength were optimized. Compared with conventional methods, this approach exhibited low limits of detection (0.001-0.1 µg/L), good recoveries (86.2-103.6%), high enrichment factors (25-50), and negligible matrix effects (-12.3-13.7%). The proposed method was demonstrated to provide a rapid, practical, and environmentally friendly procedure due to no acid reagent, toxic solvent, or external energy requirement, giving rise to potential application on other high acid-content matrices.


Assuntos
Sucos de Frutas e Vegetais/análise , Inseticidas/análise , Microextração em Fase Líquida , Neonicotinoides/análise , Cromatografia Líquida de Alta Pressão , Concentração de Íons de Hidrogênio , Inseticidas/metabolismo , Neonicotinoides/metabolismo
10.
Int J Therm Sci ; 137: 534-538, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32021553

RESUMO

NASA is designing an unmanned submarine to explore the depths of the hydrocarbon-rich seas on Saturn's moon Titan. Data from Cassini indicates that the Titan north polar environment sustains stable seas of variable concentrations of ethane, methane, and nitrogen, with a surface temperature near 93 K. The submarine must operate autonomously, study atmosphere/sea exchange, interact with the seabed, hover at the surface or any depth within the sea, and be capable of tolerating variable hydrocarbon compositions. Currently, the main thermal design concern is the effect of effervescence on submarine operation, which affects the ballast system, science instruments, and propellers. Twelve effervescence measurements on various liquid methane-ethane compositions with dissolved gaseous nitrogen are thus presented from 1.5 bar to 4.5 bar at temperatures from 92 K to 96 K to simulate the conditions of the seas. After conducting effervescence measurements, two freezing point depression measurements were conducted. The freezing liquid line was depressed more than 15 K below the triple point temperatures of pure ethane (90.4 K) and pure methane (90.7 K). Experimental effervescence measurements will be used to compare directly with effervescence modeling to determine if changes are required in the design of the thermal management system as well as the propellers.

11.
Plant Cell Environ ; 41(6): 1361-1368, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29424925

RESUMO

Since 1988, researchers have exposed stems to positive pressures to displace water in vessels and measure the impact of applied pressure on hydraulic conductivity. The pressure-sleeve technique has been used in more than 60 publications to measure vulnerability curves (VCs), which are a measure of how water stress impacts the ability of plants to transport water because water stress induces embolism in vessels that blocks water flow. It is thought that the positive pressure in a sleeve required to induce 50% loss of conductivity (PLC), P50 , is the same magnitude as the tension that causes 50% PLC, T50 , where the tension can be induced by either bench-top dehydration or by a centrifuge technique. The unifying concept that P50  = T50 and that the entire VC is the same regardless of method is referred to as the air-seeding hypothesis. In the current study, we performed experiments to further test the air-seeding hypothesis in pressure sleeves and concluded that an "effervescence" mechanism caused embolism formation under positive pressure. This mechanism explains why VCs measured using positive pressure do not always match VCs obtained by other methods that induce water tension.


Assuntos
Acer/fisiologia , Ar , Pressão , Xilema/fisiologia , Caules de Planta/fisiologia , Especificidade da Espécie , Fatores de Tempo , Água
12.
Anal Bioanal Chem ; 410(12): 2921-2935, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29532194

RESUMO

Herein, a novel magnetic effervescence tablet-assisted microextraction coupled to in situ metathesis reaction of ionic liquid (IS-META-ILDM) is presented for the determination of four endogenous steroids in human urine, pregnant women's blood, and fetal umbilical cord blood. The magnetic effervescent tablets, which were composed of Fe3O4 nanoparticles, sodium carbonate (alkaline source), and tartaric acid (acidic source), were used to disperse the extractant and for convenient magnetic separation. After the effervescent reaction, in situ reaction between NH4PF6 and [C6MIM]BF4 was adopted to change hydrophilic ionic liquid to hydrophobic liquid, which could be separated from the aqueous phase. The newly developed method has three obvious advantages: (1) combination of effervescent dispersion and magnetic nanoparticles' retrieval is cost-effective and the dispersion and collection of the extractant can be completed almost simultaneously; (2) as compared to temperature-controlled ionic liquid dispersive microextraction and cold-induced solidified microextraction, this method avoids a heating and cooling process which significantly reduces the extraction time and energy cost; and (3) the combination of adsorption by magnetic nanoparticles with extraction by in situ metathesis reaction easily produces high recoveries for target analytes. The optimized composition of effervescent tablet and experimental parameters are as follows: 0.64 g mixture of sodium carbonate and tartaric acid, 7 mg of Fe3O4 (20 nm) as magnetic sorbents, 40 µL of [C6MIM]BF4 as the extraction solvent, 0.15 g NH4PF6, and 300 µL of elution solvent. Under the optimized conditions, the newly developed method provided high extraction recoveries (90.0-118.5%) and low LODs (0.14-0.17 µg L-1) in urine and blood samples. In total, this IS-META-ILDM method provided high extraction efficiency, fast and convenient separation, and underutilization of any organic solvent, and thus it has great potential for the determination of trace endogenous steroids in complex human fluids. Graphical abstract The newly developed method has three obvious advantages: combination of effervescent dispersion and magnetic nanoparticles' retrieval is cost-effective and the dispersion and collection of the extractant can be completed almost simultaneously. It avoids a heating and cooling process which significantly reduces the extraction time and energy cost and easily produces high recoveries for target analytes.


Assuntos
Líquidos Iônicos/química , Microextração em Fase Líquida/instrumentação , Nanopartículas de Magnetita/química , Esteroides/sangue , Esteroides/urina , Cromatografia Líquida de Alta Pressão/instrumentação , Cromatografia Líquida de Alta Pressão/métodos , Desenho de Equipamento , Feminino , Hormônios/sangue , Hormônios/isolamento & purificação , Hormônios/urina , Humanos , Limite de Detecção , Microextração em Fase Líquida/métodos , Magnetismo/instrumentação , Magnetismo/métodos , Masculino , Gravidez , Esteroides/isolamento & purificação
13.
Anal Bioanal Chem ; 410(11): 2671-2687, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29511836

RESUMO

This study developed a new effervescence-assisted switchable fatty acid-based microextraction combined with solidification of a floating organic-droplet (EA-SFAM-SFO) for simple and rapid determination of fluoroquinolones and tetracyclines in seawater, sediment, and seafood. Five medium-chain fatty acids (pentanoic acid, hexanoic acid, heptanoic acid, octanoic acid, and nonanoic acid) were tested as an extraction solvent, given their ability to change between hydrophobic and hydrophilic forms by pH adjustment. As nonanoic acid had the highest extraction recovery (>92%) for the six antibiotics and the ability to transform from liquid to a solidified floating state at low temperature, it was selected as the optimum extraction solvent. The prominent advantages of the newly developed method are: (1) reaction between the procedures salt and fatty acid changed extraction solvent from the hydrophobic to hydrophilic state; (2) bubbling with CO2 greatly increased the contact area between fatty acid and analytes resulting in improved extraction recovery; and (3) solidification of the fatty acid at a low temperature provided good separation and avoided the use of specialized equipment. Single-factor screening and optimization of the main factors were conducted using Plackett-Burman design and central composite design, respectively. The main parameters were optimized as follows: 258 µL fatty acid, 406 µL H2SO4 (98%), 3.9 min vortex time, and 354 µL Na2CO3 (2 mol L-1). Under optimized conditions, limits of detection were 0.007-0.113 µg L-1 or µg kg-1 and extraction recoveries were 82.2%-116.7% for six fluoroquinolone and tetracycline antibiotics in seawater, sediments, and seafood. The newly developed method combines the advantages of effervescence-assisted dispersion, hydrophobic/hydrophilic switchable solvent, and liquid/solid transition induced by low temperature. Overall, the new method is simple, quick, and environment-friendly with low detection limits and high recoveries. Thus, the newly developed method has excellent prospects for sample pretreatment and analysis of antibiotics in marine environmental and food samples. Graphical Abstract ᅟ.


Assuntos
Antibacterianos/análise , Fluoroquinolonas/análise , Sedimentos Geológicos/análise , Alimentos Marinhos/análise , Água do Mar/análise , Tetraciclinas/análise , Poluentes Químicos da Água/análise , Cromatografia Líquida de Alta Pressão/economia , Cromatografia Líquida de Alta Pressão/métodos , Ácidos Graxos/química , Limite de Detecção , Microextração em Fase Líquida/economia , Microextração em Fase Líquida/métodos , Solventes/química
14.
J Sep Sci ; 39(22): 4422-4428, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27670749

RESUMO

In this study, a simple effervescence-assisted dispersive solid-phase extraction method was developed to detect fungicides in honey and juice. Most significantly, an innovative ionic-liquid-modified magnetic ß-cyclodextrin/attapulgite sorbent was used because its large specific surface area enhanced the extraction capacity and also led to facile separation. A one-factor-at-a-time approach and orthogonal design were employed to optimize the experimental parameters. Under the optimized conditions, the entire extraction procedure was completed within 3 min. In addition, the calibration curves exhibited good linearity, and high enrichment factors were achieved for pure water and honey samples. For the honey samples, the extraction efficiencies for the target fungicides ranged from 77.0 to 94.3% with relative standard deviations of 2.3-5.44%. The detection and quantitation limits were in the ranges of 0.07-0.38 and 0.23-1.27 µg/L, respectively. Finally, the developed technique was successfully applied to real samples, and satisfactory results were achieved. This analytical technique is cost-effective, environmentally friendly, and time-saving.


Assuntos
Contaminação de Alimentos/análise , Sucos de Frutas e Vegetais/análise , Fungicidas Industriais/análise , Mel/análise , Cromatografia Líquida de Alta Pressão , Compostos de Magnésio/química , Compostos de Silício/química , Extração em Fase Sólida , beta-Ciclodextrinas/química
15.
J Sep Sci ; 39(23): 4603-4609, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27734583

RESUMO

A pretreatment method named tablet-effervescence-assisted dissolved carbon flotation was introduced for the determination of four triazole fungicides in environmental water. In this method, the use of effervescent tablet composed of nontoxic sodium carbonate and sodium dihydrogen phosphate could generate CO2 in situ to assist the dispersion of extraction solvent and to accelerate mass transfer of target analytes. In addition, the simple phase separation simply based on the rising of low-density organic solvent from the aqueous phase was applied rather than the application of apparatus, which demonstrated the potential for on-site extraction in the field. The experimental variables, including the composition of effervescent tablets, amount of effervescent tablets, types and volume of extraction solvent, were investigated. Under the optimized conditions, the method showed good linearity for myclobutanil, tebuconazole, epoxiconazole, and difenoconazole in the range of 1-100 µg/L. The limits of detection and the limits of quantification were within the range of 0.15-0.26 and 0.49-0.86 µg/L, respectively. The obtained correlation coefficients varied from 0.997 to 0.999, and suitable enrichment factors were 422-589. The recoveries were 82.5-112.9% with relative standard deviations of 4.7-13.5%.


Assuntos
Fungicidas Industriais/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Triazóis/isolamento & purificação , Carbono , Cromatografia Líquida de Alta Pressão , Comprimidos , Água
16.
Cogn Emot ; 30(1): 20-32, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25787295

RESUMO

We investigated the intensely positive emotional experiences arising from participation in a large-scale collective event. We predicted such experiences arise when those attending a collective event are (1) able to enact their valued collective identity and (2) experience close relations with other participants. In turn, we predicted both of these to be more likely when participants perceived crowd members to share a common collective identity. We investigated these predictions in a survey of pilgrims (N = 416) attending a month-long Hindu pilgrimage festival in north India. We found participants' perceptions of a shared identity amongst crowd members had an indirect effect on their positive experience at the event through (1) increasing participants' sense that they were able to enact their collective identity and (2) increasing the sense of intimacy with other crowd members. We discuss the implications of these data for how crowd emotion should be conceptualised.


Assuntos
Emoções , Processos Grupais , Identificação Social , Percepção Social , Idoso , Feminino , Humanos , Relações Interpessoais , Masculino , Comportamento de Massa , Comportamento Social
17.
Br J Sociol ; 67(2): 328-47, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27121256

RESUMO

Research on partying and nightlife often emphasizes commercial control while overlooking participants' creativity and agency. Due to their age, appearance and transgressive partying, participants in the Norwegian high school graduation celebration have limited access to bars and pubs in the ordinary night-time economy. To create alternative party spaces under their own control they utilize the spatial opportunities offered by automobility. Groups of students get together many years in advance and buy old buses which they refurbish to become rolling nightclubs that enable them to 'transcend space' through partying while on the move. These mobile party spaces provide a material and symbolic centre of communion and a tight space for physical assembly that enhances the production of intense positive emotions. In a cat-and-mouse game with the police, the buses provide a sense of nomadic autonomy, and enable participants to drink heavily for days on end. The study examines how youth may creatively zone their own party spaces within the context of automobility and how these mobile spaces again shape the partying that goes on within them. While this party practice opens up for autonomy, creativity and social transgressions reminiscent of liminal phases or carnivals, at a deeper level participants clearly reproduce class-based differences and exaggerate conventional practices and symbols.


Assuntos
Comportamento do Adolescente/psicologia , Comportamento Social , Estudantes/psicologia , Consumo de Álcool por Menores/psicologia , Adolescente , Atitude , Feminino , Humanos , Entrevistas como Assunto , Masculino , Veículos Automotores , Noruega , Polícia , Recreação , Instituições Acadêmicas , Classe Social , Meios de Transporte
18.
AAPS PharmSciTech ; 16(6): 1487-94, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26265190

RESUMO

The solubility of five poorly soluble drugs was enhanced by using an effervescence assisted solid dispersion (EASD) technique. EASDs were prepared by using modified fusion method. Drug and hydrophilic carrier were melted, and in this molten mixture, effervescence was generated by adding effervescence couple comprising organic acid (citric acid) and carbonic base (sodium bicarbonate). Solubility of drug powders, solid dispersions, and EASDs was determined at 25°C using shake flask method. Atorvastatin calcium, cefuroxime axetil, clotrimazole, ketoconazole, and metronidazole benzoate were estimated using a spectrophotometer at 246, 280, 260, 230, and 232 nm (λ max), respectively. Solubility of atorvastatin calcium (from 100 to 345 µg/ml), cefuroxime axetil (from 441 to 1948 µg/ml), clotrimazole (from 63 to 677 µg/ml), ketoconazole (from 16 to 500 µg/ml), and metronidazole benzoate (from 112 to 208 µg/ml) in EASDs was enhanced by 3.45-, 4.4-, 10.7-, 31.2-, and 1.8-fold, respectively. Scanning electron micrographs of drug powder, solid dispersion, and EASDs were compared. Scanning electron micrographs of EASDs showed a uniform distribution of drug particles in the carrier matrix. Morphology (size and shape) of cefuroxime axetil particles was altered in solid dispersion as well as in EASD. EASDs showed better solubility enhancement than conventional solid dispersions. The present technique is better suitable for drugs having a low melting point or melt without charring. Effervescence assisted fusion technique of preparing solid dispersions can be employed for enhancing solubility, dissolution, and bioavailability of poorly soluble drugs.


Assuntos
Química Farmacêutica/métodos , Preparações Farmacêuticas/química , Tecnologia Farmacêutica/métodos , Disponibilidade Biológica , Varredura Diferencial de Calorimetria/métodos , Portadores de Fármacos/química , Interações Hidrofóbicas e Hidrofílicas , Pós/química , Solubilidade
19.
J Sep Sci ; 37(21): 3157-63, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25136817

RESUMO

A novel effervescence-assisted dispersive liquid-liquid microextraction method has been developed for the determination of four fungicides in apple juice samples. In this method, a solid effervescent agent is added into samples to assist the dispersion of extraction solvent. The effervescent agent is environmentally friendly and only produces an increase in the ionic strength and a negligible variation in the pH value of the aqueous sample, which does not interfere with the extraction of the analytes. The parameters affecting the extraction efficiency were investigated including the composition of effervescent agent, effervescent agent amount, formulation of effervescent agent, adding mode of effervescent agent, type and volume of extraction solvent, and pH. Under optimized conditions, the method showed a good linearity within the range of 0.05-2 mg/L for pyrimethanil, fludioxonil, and cyprodinil, and 0.1-4 mg/L for kresoxim-methyl, with the correlation coefficients >0.998. The limits of detection for the method ranged between 0.005 and 0.01 mg/L. The recoveries of the target fungicides in apple juice samples were in the range of 72.4-110.8% with the relative standard deviations ranging from 1.2 to 6.8%.


Assuntos
Bebidas/análise , Contaminação de Alimentos/análise , Fungicidas Industriais/análise , Fungicidas Industriais/isolamento & purificação , Microextração em Fase Líquida/métodos , Malus/química , Cromatografia Líquida de Alta Pressão , Microextração em Fase Líquida/instrumentação
20.
Saudi Pharm J ; 22(1): 53-61, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24493974

RESUMO

The present study aimed to formulate orodispersible tablets of flutamide (FTM) to increase its bioavailability. Orodispersible tablets were prepared by direct compression technique using three different approaches namely; super-disintegration, effervescence and sublimation. Different combined approaches were proposed and evaluated to optimize tablet characteristics. Sodium starch glycolate (SSG) was used as the superdisintegrant. The prepared powder mixtures were subjected to both pre and post compression evaluation parameters including; IR spectroscopy, micromeritics properties, tablet hardness, friability, wetting time, disintegration time and in-vitro drug release. IR studies indicated that there was no interaction between the drug and the excipients used except Ludipress. The results of micromeritics studies revealed that all formulations were of acceptable to good flowability. Tablet hardness and friability indicated good mechanical strength. Wetting and dispersion times decreased from 46 to 38 s by increasing the SSG concentration from 3.33 to 6.66% w/w in tablets prepared by superdisintegration method. The F8 formulation which was prepared by combined approaches of effervescence and superdisintegrant addition gave promising results for tablet disintegration and wetting times but failed to give faster dissolution rate. The incorporation of 1:5 solid dispersion of FTM: PEG 6000 instead of the pure drug in the same formulation increased the drug release rate from 73.12 to 96.99% after 15 min. This increase in the dissolution rate may be due to the amorphization of the drug during the solid dispersion preparation. The presence of the amorphous form of the drug was shown in the IR spectra.

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