55 research outputs found
Design and Implementation of Wave Digital Filters
One of possibilities of the Wave Digital Filters (WDF) design is using the classical LC-filters theory. The aim of this paper is to demonstrate the design of WDF from the LC filter and the implementation of WDF on the fixed-point digital signal processor. The theory of wave digital filter has been developed by using the classical scattering parameter theory. The theory of ladder filters is well-known, and so our present problem can thus be reduced to a problem how to replace the L and C elements of the filters by adaptors and delay elements, adders and multipliers
Pullulan-based nanoparticles as carriers for transmucosal protein delivery
Polymeric nanoparticles have revealed very effective in transmucosal delivery of
proteins. Polysaccharides are among the most used materials for the production of these
carriers, owing to their structural flexibility and propensity to evidence biocompatibility
and biodegradability. In parallel, there is a preference for the use of mild methods for
their production, in order to prevent protein degradation, ensure lower costs and easier
procedures that enable scaling up.
In this work we propose the production of pullulan-based nanoparticles by a mild
method of polyelectrolyte complexation. As pullulan is a neutral polysaccharide,
sulfated and aminated derivatives of the polymer were synthesized to provide pullulan
with a charge. These derivatives were then complexed with chitosan and carrageenan,
respectively, to produce the nanocarriers. Positively charged nanoparticles of 180-270
nm were obtained, evidencing ability to associate bovine serum albumin, which was
selected as model protein. In PBS pH 7.4, pullulan-based nanoparticles were found to
have a burst release of 30% of the protein, which maintained up to 24h. Nanoparticle
size and zeta potential were preserved upon freeze-drying in the presence of appropriate
cryoprotectants. A factorial design was approached to assess the cytotoxicity of raw
materials and nanoparticles by the metabolic test MTT. Nanoparticles demonstrated to
not cause overt toxicity in a respiratory cell model (Calu-3). Pullulan has, thus,
demonstrated to hold potential for the production of nanoparticles with an application in
protein delivery
Lampreys, the jawless vertebrates, contain three Pax6 genes with distinct expression in eye, brain and pancreas
10.1038/s41598-019-56085-8Scientific Reports911955
Зміни поведінки споживачів: традиційні та нові фактори в динамічному маркетинговом ландшафті за останні 15 років
Стаття узагальнює фактори, що впливають на рішення споживачів щодо покупок, та зміни, які ці фактори
зазнали протягом останніх 15 років. Дослідження спрямоване на визначення змін, які відбулися в
маркетинговому ландшафті та факторів, що впливають на рішення споживачів щодо покупок протягом останніх
15 років, і виявлення нових факторів, які впливають на рішення споживачів щодо покупок на сьогоднішній день.
Дослідження було проведено за допомогою анкетного опитування, яке відбулося в Чеській Республіці (N = 686).
Методичним інструментарієм дослідження стали методи описової статистики та багатофакторного аналізу.
Емпіричні результати дослідження засвідчили, що між 2007 і 2022 роками не було значущих змін у сприйнятті
споживачами важливості традиційних факторів, що впливають на їх рішення щодо покупок в різних категоріях
продукції. Дослідження підтвердило, що споживачі сприймають якість, ціну та необхідність як найважливіші
фактори в різних категоріях, тоді як реклама залишалася найменш важливою. Однак важливість реклами зросла
для деяких категорій товарів, таких як одяг, взуття та транспорт, разом із зростанням важливості знижок. Проте
перед прийняттям рішення про покупку виникли нові фактори, що впливають на поведінку споживачів.
Категорія товарів одягу та взуття була обрана для докладного факторного аналізу через те, що споживачі
приділяли більше уваги новим факторам саме в цій категорії, ніж в інших категоріях товарів. Застосовуючи
факторний аналіз, автори визначили п'ять факторів рішення споживачів щодо покупки в даній категорії. Першим
фактором, який є вирішальним при здійсненні покупки, були поточні тенденції на ринку. Другим – рекомендації,
включаючи рекомендації від сім'ї, друзів і професіоналів, а також можливість спробувати щось нове. Третім –
досвід, оснований на попередньому досвіді споживача, який також визначав пізніше обрані параметри і якість
продукту. Четвертим – ціноутворення. Останнім фактором рішення про покупку є стійкість як у споживанні, так
і в покупці. Результати дослідження корисні для учасників ринку, особливо при формуванні комунікаційної
стратегії компанії.This paper summarises the factors influencing consumer purchasing decisions and the changes
that these factors have undergone over the last 15 years. The research aimed to determine what changes have
occurred in the intensity of the traditional factors influencing consumers’ purchasing decisions over the past
15 years and to identify the new factors currently shaping consumers’ purchasing decisions. The research
was carried out by means of a questionnaire survey conducted in the Czech Republic (N = 686). The survey
results were subjected to descriptive statistics combined with multivariate exploratory factor analysis. The
paper presents the results of an empirical analysis that showed that between 2007 and 2022, there were no
significant changes in consumers’ perceived importance of traditional factors influencing their purchasing
decisions in different categories of consumption. The research has confirmed that consumers perceived
quality, price and necessity as the most important factors across the different categories, while advertising
was still the least important. However, the perceived importance of advertising has increased slightly in some
shopping categories, such as clothing and footwear and transport, along with the perceived importance of
discounts. However, new factors have emerged to influence consumers before making a purchase decision.
The clothing and footwear category was selected for detailed factor analysis because consumers assigned
more importance to the emerging factors here than other purchase categories. By applying factor analysis,
the authors identified five determinants of consumer decision-making in purchasing clothing and footwear
categories, including new and traditional factors. The first determinant was the current trends in the market.
The second determinant was recommendations, including recommendations from family, friends and
professionals, together with the chance to try something new. The third purchase determinant was experience
based on the consumer’s previous experience, which also shaped the subsequently preferred parameters and
product quality. The fourth determinant was pricing. The final determinant of the purchase decision was
sustainability in both consumption and purchase. The research results are useful for market players,
especially in the innovation of customer communication and company marketing management
Protective effect of diallyl trisulfide against naphthalene-induced oxidative stress and inflammatory damage in mice
Bidirectional link between upper and lower airways in patients with allergic rhinitis
Abstract Objective Exhaled nitric oxide has been proposed as a noninvasive marker of eosinophilic airway inflammation in lower airways. The aim of the study was to investigate the impact of atopy, pollen exposure, and pharmacological treatment on NO production in lower airways of patients with allergic rhinitis. Subjects and methods Measurements of exhaled NO were performed in 79 non-asthmatic subjects with seasonal allergic rhinitis outside and in pollen season, before and after pharmacological treatment, and in 54 healthy controls. Results Patients with allergic rhinitis had significantly higher levels of exhaled NO (18.3 ± 11.0 ppb) than healthy controls (13.0 ± 7.2 ppb) measured outside the pollen season (P = 0.0024). Increased exhaled NO levels were also found in patients with allergic rhinitis in the pollen season (27.0 ± 20.0 ppb) compared with the levels outside pollen season (P = 0.0001), before pharmacological treatment. In rhinitic patients treated by nasal corticosteroids and antihistamines in the pollen season, the levels of exhaled NO were significantly lower (17.0 ± 16.4 ppb; P = 0.045) than those before treatment. No difference was found in NO levels in rhinitic patients outside and in pollen season after pharmacological treatment. Conclusions This study has shown the presence of eosinophilic airway inflammation in the lower airways in allergic rhinitis patients. A significant increase of exhaled NO after pollen exposure in rhinitic patients underlies the impact of inflammation on the upper respiratory tract. A bidirectional link between upper and lower airways is confirmed by a decrease in exhaled NO in the pollen season, almost to the starting levels, after application of topic corticosteroids and antihistamines.</p
Finite Word-Length Effects in Digital State-Space Filters
The state-space description of digital filters involves except the relationship between input and output signals an additional set of state variables. The state-space structures of digital filters have many positive properties compared with direct canonical structures. The main advantage of digital filter structures developed using state-space technique is a smaller sensitivity to quantization effects by fixed-point implementation. In our presentation, the emphasis is on the analysis of coefficient quantization and on existence of zero-input limit cycles in state-space digital filters. The comparison with direct form II structure is presented
Screening of Commercial Enzymes for Transfructosylation of Tyrosol: Effect of Process Conditions and Reaction Network
Anti-amyloidogenic activity of glutathione-covered gold nanoparticles
This study is an investigation of the effect of biocompatible glutathione-covered gold nanoparticles (AuSG_7) with an average size of 3 nm on the amyloid fibrils of hen egg-white lysozyme. The anti-amyloid activity of AuSG_7 nanoparticles on this protein was monitored with thioflavin T assay, atomic force microscopy and transmission electron microscopy. The study found that AuSG_7 nanoparticles in vitro depolymerize the amyloid aggregates and inhibit lysozyme aggregate formation. The ability to inhibit amyloid formation and promote amyloid disassembly has concentration-dependent characteristics: the concentration of nanoparticles at which inhibition is half maximal (IC50) was found to be 6.19 mu g/mL, and the concentration at which depolymerization is half maximal (DC50) was found to be 826 mu g/ml. (C) 2012 Elsevier B.V. All rights reserved
Mizolastine provides effective symptom relief in patients suffering from perennial allergic rhinitis: a double-blind, placebo-controlled study versus loratadine.
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