32 research outputs found
Panic Buying in Hungary During Covid-19 Pandemic
The study examines buyers’ behavior in Hungary during COVID -19 pandemic based on a non-representative online questionnaire that was carried out during the time of lockdown in Hungary in March 2020. We would like to find out whether there was really accumulation of goods, and if so, which product ranges were involved. How did the outbreak of COVID-19 change shopping behavior? In which direction did it move and could retail trade react to the unexpected, rapid challenge of going online? Can the respondents be identified with the traditional buying behaviour pattern and can it be typified with it? In our study we provide an overview of the anomalies detected in the Hungarian “panic buying” concerning shopping frequency, spending and product avoidance. First, we introduce the main behavioral patterns of shoppers during the “panic buying period” in Hungary, then we draft different types of customers. Second, we highlight some statistically significant relations with regional aspects. Here connections are identified between shopping frequency, spending, stock piling and the places of residency of the surveyed people. Third, we categorised customers into five groups with cluster analysis. The main cluster forming differences are the altered sense of well-being and the attitude differences in stock piling
Gelatin content governs hydration induced structural changes in silica-gelatin hybrid aerogels – Implications in drug delivery
Silica-gelatin hybrid aerogels of varying gelatin content (from 4 wt.% to 24 wt.%) can be conveniently impregnated with hydrophobic active agents (e.g. ibuprofen, ketoprofen) in supercritical CO2 and used as drug delivery systems. Contrast variation neutron scattering (SANS) experiments show the molecular level hybridization of the silica and the gelatin components of the aerogel carriers. The active agents are amorphous, and homogeneously dispersed in these porous, hybrid matrices. Importantly, both fast and retarded drug release can be achieved with silica-gelatin hybrid aerogels, and the kinetics of drug release is governed by the gelatin content of the carrier. In this paper, for the first time, a molecular level explanation is given for the strong correlation between the composition and the functionality of a family of aerogel based drug delivery systems. Characterization of the wet aerogels by SANS and by NMR diffusiometry, cryoporometry and relaxometry revealed that the different hydration mechanisms of the aerogels are responsible for the broad spectrum of release kinetics. Low-gelatin (4–11 wt.%) aerogels retain their open-porous structure in water, thus rapid matrix erosion dictates fast drug release from these carriers. In contrast to this, wet aerogels of high gelatin content (18–24 wt.%) show well pronounced hydrogel-like characteristics, and a wide gradual transition zone forms in the solid-liquid interface. The extensive swelling of the high-gelatin hybrid backbone results in the collapse of the open porous structure, that limits mass transport towards the release medium, resulting in slower, diffusion controlled drug release
Mechanism of hydration of biocompatible silica-casein aerogels probed by NMR and SANS reveal backbone rigidity
Starting from TMOS and implementing co-gelation in the sol-gel method, silica was hybridized with an industrial formulation of bovine casein. The hybrid alcogels were dried in supercritical CO2 to yield crack-free silica-casein aerogel monoliths of casein contents ranging from 4.7 wt% to 28 wt%. Cross-linked hybrid aerogels were produced from formaldehyde treated alcogels. The microstructures and the morphologies of the silica-casein aerogels highly resemble to that of pristine silica aerogels. The primary building blocks are spherical particles that interconnect into mesoporous networks (average dpore = 20 nm and SBET = 700 nm2/g), as shown by SEM, small-angle neutron scattering (SANS) and N2 adsorption-desorption porosimetry. Contrast variation SANS experiments show that silica and casein form homogeneous nanocomposite backbones. The interaction of water with silica-casein aerogels was investigated by SANS, and by NMR cryoporometry, relaxometry and diffusiometry. Even when fully saturated with water, the hybrid silica-casein aerogels retain their original, highly permeable, open mesoporous structures that formed under supercritical drying. This represents a unique and advantageous wetting mechanism among hybrid inorganic-biopolymer materials, since the strong hydration of the biopolymer component often causes the deformation of the backbone and the consequent collapse of the porous structure. Silica-casein aerogels are biocompatible and inert for CHO-K1 cells