147 research outputs found
Consumer satisfaction and word-of-mouth in Electronic Commerce: a possible segmentation method
Over the last 10 years the B2C online market and its characteristics – for example the
perceived electronic service quality (e-SQ) – has become a relevant research area, not only in
the Western countries but also in smaller, less-developed countries. Therefore the first aim of
this paper is to provide a description of an analysis into how the dimensions of perceived eSQ
relate to satisfaction and WOM intention in Hungary. Secondly, using the results of a
PLS-SEM model we show how consumers may be segmented based on their perceptions of
quality. According to our research only the dimension of efficiency and responsiveness have a
significant positive effect on satisfaction, and the perception of the quality of fulfilment’s also
significantly influences word-of-mouth intention. Using the relevant latent variable scores a
segmentation method was developed in which four significantly different segments were
identified
Hőmérséklet szerepének vizsgálata a gabonafélék virágzásában = Evaluating the role of ambient temperature in determining flowering in cereals
Az árpa egyedfejlődését és így a földrajzi adaptációs képességét elsődlegesen a vernalizációs igény, valamint a nappalhossz érzékenység mértéke szabja meg. E két komponens alapján kialakított árpa csoportokon belül azonban nagy variabilitás mutatkozik a fajták egyedfejlődési mintázatában és virágzási idejében. Kísérleteinkkel célunk volt e variabilitást kiváltó környezeti tényezők egyedfejlődésre gyakorolt hatásának részletes elemzése, valamint ezekre a környezeti tényezőre adott válaszreakciók genetikai szabályozásában közreműködő komponensek azonosítása. Vizsgáltuk a környezeti hőmérséklet szerepét a vernalizációs folyamatokat és a hőstresszt kiváltó hőmérsékletek közti intervallumban, az állandó és a napi fluktuáló tényezők (fény, hőmérséklet) egymáshoz viszonyított hatását, valamint a fény minőségének a szerepét. Meghatároztuk e környezeti tényezőkre adott válaszreakciók természetes variabilitásának mértékét a termesztett árpafajták körében, kontrasztos reakciójú fajtákat azonosítottunk a további kísérletek céljaira. Kétszülős árpa populációkra alapozott QTL elemzéssel, és nagy fajtakört magába foglaló gyűjteményre alapozott teljes genomra kiterjedő fenotípus – genotípus asszociációs elemzésekkel azonosítottuk a szabályozásban szerepet játszó főbb genetikai komponenseket. Nyomon követtük a főbb egyedfejlődési gének génexpressziós mintázatainak változását mesterséges (kontrollált klímakamra) és természetes (szántóföldi vegetációs periódus) környezetben, több vetésidőben. | In cereals, plant development and thus the ecological adaptation is basically determined by the vernalization requirement and photoperiod sensitivity. Large variation in flowering time exists however between the cultivars within the various groups of these two factors. Our major aims were to identify the additional environmental cues responsible for this variation, to characterise their effects on plant developmental patterns and to evaluate the genetic determinants participating in the regulation pathways of these environmental cues. Thus we studied the effects of ambient temperature on plant development in the range between its function as a vernalising agent and being an abiotic stress factor, the effects of daily fluctuating factors (light and temperature) compared to constant environment, and the effects of the quality of light. We characterised the natural variation present in cultivated barley for these environmental factors and identified contrasting types for further studies. The evaluation of the genetic components involved was carried out partly by QTL studies in bi-parental mapping populations and partly by genome wide association mapping in a multi-parental barley collection. Changes in the expression levels of the major plant developmental genes were also followed both in controlled environmental tests and under field conditions during the vegetation period with the application of different sowing time
A Stereolithography-Based Modified Spin-Casting Method for Faster Laboratory-Scale Production of Dexamethasone-Containing Dissolving Microneedle Arrays
Microneedle arrays (MNAs) consist of a few dozens of submillimeter needles, which tend to penetrate through the stratum corneum layer of the skin and deliver hardly penetrating drugs to the systemic circulation. The application of this smart dosage form shows several advantages, such as simple use and negligible pain caused by needle punctures compared to conventional subcutaneous injections. Dissolving MNAs (DMNAs) represent a promising form of cutaneous drug delivery due to their high drug content, biocompatibility, and ease of use. Although different technologies are suitable to produce microneedle arrays (e.g., micromilling, chemical etching, laser ablation etc.), many of these are expensive or hardly accessible. Following the exponential growth of the 3D-printing industry in the last decade, high-resolution desktop printers became accessible for researchers to easily and cost-effectively design and produce microstructures, including MNAs. In this work, a low force stereolithography (LFS) 3D-printer was used to develop the dimensionally correct MNA masters for the spin-casting method. The present study aimed to develop and characterize drug-loaded DMNAs using a two-level, full factorial design for three factors focusing on the optimization of DMNA production and adequate drug content. For the preparation of DMNAs, carboxymethylcellulose and trehalose were used in certain amounts as matrices for dexamethasone sodium phosphate (DEX). Investigation of the produced DexDMNAs included mechanical analysis via texture analyzer and optical microscopy, determination of drug content and distribution with HPLC and Raman microscopy, dissolution studies via HPLC, and ex vivo qualitative permeation studies by Raman mapping. It can be concluded that a DEX-containing, mechanically stable, biodegradable DexDMNA system was successfully developed in two dosage strengths, of which both efficiently delivered the drug to the lower layers (dermis) of human skin. Moreover, the ex vivo skin penetration results support that the application of DMNAs for cutaneous drug delivery can be more effective than that of a conventional dermal gel
Comparative Study of TPGS and Soluplus Polymeric Micelles Embedded in Poloxamer 407 In Situ Gels for Intranasal Administration
This study aims to highlight the importance of choosing the appropriate co-polymer or co-polymer mixed combinations in order to design value-added nasal dosage forms. Local therapy of upper respiratory tract-related infections, such as nasal rhinosinusitis is of paramount importance, thus advanced local therapeutic options are required. Dexamethasone was encapsulated into three different polymeric micelle formulations: Soluplus or TPGS-only and their mixed combinations. Dynamic light scattering measurements proved that the particles have a micelle size less than 100 nm in monodisperse distribution, with high encapsulation efficiency above 80% and an at least 7-fold water solubility increase. Tobramycin, as an antimicrobial agent, was co-formulated into the in situ gelling systems which were optimized based on gelation time and gelation temperature. The sol–gel transition takes place between 32–35 °C, which is optimally below the temperature of the nasal cavity in a quick manner below 5 min, a suitable strategic criterion against the mucociliary clearance. In vitro drug release and permeability studies confirmed a rapid kinetics in the case of the encapsulated dexamethasone accompanied with a sustained release of tobramycin, as the hydrophilic drug
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